Adds Track-Only App Support (Addresses #119 and Sets Groundwork for #44) (#123)

- All Sources now have a "Track-Only" option that will prevent Obtainium from looking for APKs (though the App must still have a release of some kind so that a version string can be grabbed).
    - These Apps cannot be installed through Obtainium, but update notifications will still be sent.
    - The user needs to manually mark them as updated when appropriate.
    - This addresses issue #119.
    - It also partially addresses #44 by allowing some sources to be configured as "Track-Only"-only. The first such source (APKMirror) will be added later.
- Includes various UI changes to accommodate the above change.
- Also makes App loading a bit more responsive (sending Obtainium to the background then returning will now cause App re-load to pick up changes in App versioning that may have been made in the meantime, for instance through update checking).

.gitignore

@@ -9,6 +9,7 @@
 .history
 .svn/
 migrate_working_dir/
+.vscode/
 
 # IntelliJ related
 *.iml

lib/app_sources/fdroid.dart

@@ -48,9 +48,6 @@ class FDroid extends AppSource {
           .where((element) => element['versionName'] == latestVersion)
           .map((e) => '${apkUrlPrefix}_${e['versionCode']}.apk')
           .toList();
-      if (apkUrls.isEmpty) {
-        throw NoAPKError();
-      }
       return APKDetails(latestVersion, apkUrls);
     } else {
       throw NoReleasesError();

lib/app_sources/github.dart

@@ -11,9 +11,9 @@ class GitHub extends AppSource {
   GitHub() {
     host = 'github.com';
 
-    additionalDataDefaults = ['true', 'true', ''];
+    additionalSourceAppSpecificDefaults = ['true', 'true', ''];
 
-    moreSourceSettingsFormItems = [
+    additionalSourceSpecificSettingFormItems = [
       GeneratedFormItem(
           label: 'GitHub Personal Access Token (Increases Rate Limit)',
           id: 'github-creds',
@@ -51,7 +51,7 @@ class GitHub extends AppSource {
           ])
     ];
 
-    additionalDataFormItems = [
+    additionalSourceAppSpecificFormItems = [
       [
         GeneratedFormItem(label: 'Include prereleases', type: FormItemType.bool)
       ],
@@ -96,8 +96,8 @@ class GitHub extends AppSource {
   Future<String> getCredentialPrefixIfAny() async {
     SettingsProvider settingsProvider = SettingsProvider();
     await settingsProvider.initializeSettings();
-    String? creds =
+    String? creds = settingsProvider
-        settingsProvider.getSettingString(moreSourceSettingsFormItems[0].id);
+        .getSettingString(additionalSourceSpecificSettingFormItems[0].id);
     return creds != null && creds.isNotEmpty ? '$creds@' : '';
   }
 
@@ -155,14 +155,11 @@ class GitHub extends AppSource {
       if (targetRelease == null) {
         throw NoReleasesError();
       }
-      if ((targetRelease['apkUrls'] as List<String>).isEmpty) {
-        throw NoAPKError();
-      }
       String? version = targetRelease['tag_name'];
       if (version == null) {
         throw NoVersionError();
       }
-      return APKDetails(version, targetRelease['apkUrls']);
+      return APKDetails(version, targetRelease['apkUrls'] as List<String>);
     } else {
       rateLimitErrorCheck(res);
       throw getObtainiumHttpError(res);

lib/app_sources/gitlab.dart

@@ -33,7 +33,7 @@ class GitLab extends AppSource {
       var entry = parsedHtml.querySelector('entry');
       var entryContent =
           parse(parseFragment(entry?.querySelector('content')!.innerHtml).text);
-      var apkUrlList = [
+      var apkUrls = [
         ...getLinksFromParsedHTML(
             entryContent,
             RegExp(
@@ -48,9 +48,6 @@ class GitLab extends AppSource {
             .where((element) => Uri.parse(element).host != '')
             .toList()
       ];
-      if (apkUrlList.isEmpty) {
-        throw NoAPKError();
-      }
 
       var entryId = entry?.querySelector('id')?.innerHtml;
       var version =
@@ -58,7 +55,7 @@ class GitLab extends AppSource {
       if (version == null) {
         throw NoVersionError();
       }
-      return APKDetails(version, apkUrlList);
+      return APKDetails(version, apkUrls);
     } else {
       throw NoReleasesError();
     }

lib/app_sources/signal.dart

@@ -24,14 +24,12 @@ class Signal extends AppSource {
     if (res.statusCode == 200) {
       var json = jsonDecode(res.body);
       String? apkUrl = json['url'];
-      if (apkUrl == null) {
+      List<String> apkUrls = apkUrl == null ? [] : [apkUrl];
-        throw NoAPKError();
-      }
       String? version = json['versionName'];
       if (version == null) {
         throw NoVersionError();
       }
-      return APKDetails(version, [apkUrl]);
+      return APKDetails(version, apkUrls);
     } else {
       throw NoReleasesError();
     }

lib/app_sources/sourceforge.dart

@@ -49,9 +49,6 @@ class SourceForge extends AppSource {
           apkUrlListAllReleases // This can be used skipped for fallback support later
               .where((element) => getVersion(element) == version)
               .toList();
-      if (apkUrlList.isEmpty) {
-        throw NoAPKError();
-      }
       return APKDetails(version, apkUrlList);
     } else {
       throw NoReleasesError();

lib/components/generated_form.dart

@@ -6,6 +6,7 @@ typedef OnValueChanges = void Function(
     List<String> values, bool valid, bool isBuilding);
 
 class GeneratedFormItem {
+  late String key;
   late String label;
   late FormItemType type;
   late bool required;
@@ -25,7 +26,8 @@ class GeneratedFormItem {
       this.id = 'input',
       this.belowWidgets = const [],
       this.hint,
-      this.opts});
+      this.opts,
+      this.key = 'default'});
 }
 
 class GeneratedForm extends StatefulWidget {
@@ -209,3 +211,18 @@ class _GeneratedFormState extends State<GeneratedForm> {
         ));
   }
 }
+
+String? findGeneratedFormValueByKey(
+    List<GeneratedFormItem> items, List<String> values, String key) {
+  var foundIndex = -1;
+  for (var i = 0; i < items.length; i++) {
+    if (items[i].key == key) {
+      foundIndex = i;
+      break;
+    }
+  }
+  if (foundIndex >= 0 && foundIndex < values.length) {
+    return values[foundIndex];
+  }
+  return null;
+}

lib/components/generated_form_modal.dart

@@ -29,7 +29,7 @@ class _GeneratedFormModalState extends State<GeneratedFormModal> {
   void initState() {
     super.initState();
     values = widget.defaultValues;
-    valid = widget.initValid;
+    valid = widget.initValid || widget.items.isEmpty;
   }
 
   @override

lib/main.dart

@@ -154,6 +154,7 @@ class _ObtainiumState extends State<Obtainium> {
               0,
               ['true'],
               null,
+              false,
               false)
         ]);
       }

lib/pages/add_app.dart

@@ -2,6 +2,7 @@ import 'package:flutter/material.dart';
 import 'package:flutter/services.dart';
 import 'package:obtainium/components/custom_app_bar.dart';
 import 'package:obtainium/components/generated_form.dart';
+import 'package:obtainium/components/generated_form_modal.dart';
 import 'package:obtainium/custom_errors.dart';
 import 'package:obtainium/pages/app.dart';
 import 'package:obtainium/providers/apps_provider.dart';
@@ -22,8 +23,10 @@ class _AddAppPageState extends State<AddAppPage> {
 
   String userInput = '';
   AppSource? pickedSource;
-  List<String> additionalData = [];
+  List<String> sourceSpecificAdditionalData = [];
-  bool validAdditionalData = true;
+  bool sourceSpecificDataIsValid = true;
+  List<String> otherAdditionalData = [];
+  bool otherAdditionalDataIsValid = true;
 
   @override
   Widget build(BuildContext context) {
@@ -67,23 +70,34 @@ class _AddAppPageState extends State<AddAppPage> {
                                     ]
                                   ],
                                   onValueChanges: (values, valid, isBuilding) {
-                                    setState(() {
+                                    fn() {
                                       userInput = values[0];
                                       var source = valid
                                           ? sourceProvider.getSource(userInput)
                                           : null;
                                       if (pickedSource != source) {
                                         pickedSource = source;
-                                        additionalData = source != null
+                                        sourceSpecificAdditionalData = source !=
-                                            ? source.additionalDataDefaults
+                                                null
+                                            ? source
+                                                .additionalSourceAppSpecificDefaults
                                             : [];
-                                        validAdditionalData = source != null
+                                        sourceSpecificDataIsValid = source !=
+                                                null
                                             ? sourceProvider
                                                 .ifSourceAppsRequireAdditionalData(
                                                     source)
                                             : true;
                                       }
+                                    }
+
+                                    if (isBuilding) {
+                                      fn();
+                                    } else {
+                                      setState(() {
+                                        fn();
                                       });
+                                    }
                                   },
                                   defaultValues: const [])),
                           const SizedBox(
@@ -94,9 +108,14 @@ class _AddAppPageState extends State<AddAppPage> {
                               : ElevatedButton(
                                   onPressed: gettingAppInfo ||
                                           pickedSource == null ||
-                                          (pickedSource!.additionalDataFormItems
+                                          (pickedSource!
+                                                  .additionalSourceAppSpecificFormItems
                                                   .isNotEmpty &&
-                                              !validAdditionalData)
+                                              !sourceSpecificDataIsValid) ||
+                                          (pickedSource!
+                                                  .additionalAppSpecificSourceAgnosticDefaults
+                                                  .isNotEmpty &&
+                                              !otherAdditionalDataIsValid)
                                       ? null
                                       : () async {
                                           setState(() {
@@ -107,20 +126,52 @@ class _AddAppPageState extends State<AddAppPage> {
                                           var settingsProvider =
                                               context.read<SettingsProvider>();
                                           () async {
+                                            var userPickedTrackOnly =
+                                                findGeneratedFormValueByKey(
+                                                        pickedSource!
+                                                            .additionalAppSpecificSourceAgnosticFormItems,
+                                                        otherAdditionalData,
+                                                        'trackOnlyFormItemKey') ==
+                                                    'true';
+                                            var cont = true;
+                                            if ((userPickedTrackOnly ||
+                                                    pickedSource!
+                                                        .enforceTrackOnly) &&
+                                                await showDialog(
+                                                        context: context,
+                                                        builder:
+                                                            (BuildContext ctx) {
+                                                          return GeneratedFormModal(
+                                                            title:
+                                                                'App is Track-Only',
+                                                            items: const [],
+                                                            defaultValues: const [],
+                                                            message:
+                                                                '${pickedSource!.enforceTrackOnly ? 'Apps from this source are \'Track-Only\'.' : 'You have selected the \'Track-Only\' option.'}\n\nThe App will be tracked for updates, but Obtainium will not be able to download or install it.',
+                                                          );
+                                                        }) ==
+                                                    null) {
+                                              cont = false;
+                                            }
+                                            if (cont) {
                                               HapticFeedback.selectionClick();
-                                            App app =
+                                              App app = await sourceProvider.getApp(
-                                                await sourceProvider.getApp(
                                                   pickedSource!,
                                                   userInput,
-                                                    additionalData);
+                                                  sourceSpecificAdditionalData,
+                                                  trackOnly: pickedSource!
+                                                          .enforceTrackOnly ||
+                                                      userPickedTrackOnly);
                                               await settingsProvider
                                                   .getInstallPermission();
                                               // Only download the APK here if you need to for the package ID
                                               if (sourceProvider
-                                                .isTempId(app.id)) {
+                                                      .isTempId(app.id) &&
+                                                  !app.trackOnly) {
                                                 // ignore: use_build_context_synchronously
                                                 var apkUrl = await appsProvider
-                                                  .confirmApkUrl(app, context);
+                                                    .confirmApkUrl(
+                                                        app, context);
                                                 if (apkUrl == null) {
                                                   throw ObtainiumError(
                                                       'Cancelled');
@@ -137,17 +188,25 @@ class _AddAppPageState extends State<AddAppPage> {
                                                 throw ObtainiumError(
                                                     'App already added');
                                               }
-                                            await appsProvider.saveApps([app]);
+                                              if (app.trackOnly) {
+                                                app.installedVersion =
+                                                    app.latestVersion;
+                                              }
+                                              await appsProvider
+                                                  .saveApps([app]);
 
                                               return app;
+                                            }
                                           }()
                                               .then((app) {
+                                            if (app != null) {
                                               Navigator.push(
                                                   context,
                                                   MaterialPageRoute(
                                                       builder: (context) =>
                                                           AppPage(
                                                               appId: app.id)));
+                                            }
                                           }).catchError((e) {
                                             showError(e, context);
                                           }).whenComplete(() {
@@ -160,7 +219,11 @@ class _AddAppPageState extends State<AddAppPage> {
                         ],
                       ),
                       if (pickedSource != null &&
-                          pickedSource!.additionalDataDefaults.isNotEmpty)
+                          (pickedSource!.additionalSourceAppSpecificDefaults
+                                  .isNotEmpty ||
+                              pickedSource!
+                                  .additionalAppSpecificSourceAgnosticDefaults
+                                  .isNotEmpty))
                         Column(
                           crossAxisAlignment: CrossAxisAlignment.stretch,
                           children: [
@@ -176,19 +239,54 @@ class _AddAppPageState extends State<AddAppPage> {
                               height: 16,
                             ),
                             if (pickedSource!
-                                .additionalDataFormItems.isNotEmpty)
+                                .additionalSourceAppSpecificFormItems
+                                .isNotEmpty)
                               GeneratedForm(
-                                  items: pickedSource!.additionalDataFormItems,
+                                  items: pickedSource!
+                                      .additionalSourceAppSpecificFormItems,
                                   onValueChanges: (values, valid, isBuilding) {
+                                    if (isBuilding) {
+                                      sourceSpecificAdditionalData = values;
+                                      sourceSpecificDataIsValid = valid;
+                                    } else {
                                       setState(() {
-                                      additionalData = values;
+                                        sourceSpecificAdditionalData = values;
-                                      validAdditionalData = valid;
+                                        sourceSpecificDataIsValid = valid;
                                       });
+                                    }
                                   },
-                                  defaultValues:
+                                  defaultValues: pickedSource!
-                                      pickedSource!.additionalDataDefaults),
+                                      .additionalSourceAppSpecificDefaults),
                             if (pickedSource!
-                                .additionalDataFormItems.isNotEmpty)
+                                .additionalSourceAppSpecificFormItems
+                                .isNotEmpty)
+                              const SizedBox(
+                                height: 8,
+                              ),
+                            if (pickedSource!
+                                .additionalAppSpecificSourceAgnosticFormItems
+                                .isNotEmpty)
+                              GeneratedForm(
+                                  items: pickedSource!
+                                      .additionalAppSpecificSourceAgnosticFormItems
+                                      .map((e) => [e])
+                                      .toList(),
+                                  onValueChanges: (values, valid, isBuilding) {
+                                    if (isBuilding) {
+                                      otherAdditionalData = values;
+                                      otherAdditionalDataIsValid = valid;
+                                    } else {
+                                      setState(() {
+                                        otherAdditionalData = values;
+                                        otherAdditionalDataIsValid = valid;
+                                      });
+                                    }
+                                  },
+                                  defaultValues: pickedSource!
+                                      .additionalAppSpecificSourceAgnosticDefaults),
+                            if (pickedSource!
+                                .additionalAppSpecificSourceAgnosticDefaults
+                                .isNotEmpty)
                               const SizedBox(
                                 height: 8,
                               ),

lib/pages/app.dart

@@ -106,7 +106,7 @@ class _AppPageState extends State<AppPage> {
                           style: Theme.of(context).textTheme.bodyLarge,
                         ),
                         Text(
-                          'Installed Version: ${app?.app.installedVersion ?? 'None'}',
+                          'Installed Version: ${app?.app.installedVersion ?? 'None'}${app?.app.trackOnly == true ? ' (Estimate)\n\nApp is Track-Only' : ''}',
                           textAlign: TextAlign.center,
                           style: Theme.of(context).textTheme.bodyLarge,
                         ),
@@ -140,6 +140,7 @@ class _AppPageState extends State<AppPage> {
                       mainAxisAlignment: MainAxisAlignment.spaceEvenly,
                       children: [
                         if (app?.app.installedVersion != null &&
+                            app?.app.trackOnly == false &&
                             app?.app.installedVersion != app?.app.latestVersion)
                           IconButton(
                               onPressed: app?.downloadProgress != null
@@ -183,7 +184,8 @@ class _AppPageState extends State<AppPage> {
                               tooltip: 'Mark as Updated',
                               icon: const Icon(Icons.done)),
                         if (source != null &&
-                            source.additionalDataFormItems.isNotEmpty)
+                            source.additionalSourceAppSpecificFormItems
+                                .isNotEmpty)
                           IconButton(
                               onPressed: app?.downloadProgress != null
                                   ? null
@@ -194,11 +196,11 @@ class _AppPageState extends State<AppPage> {
                                             return GeneratedFormModal(
                                                 title: 'Additional Options',
                                                 items: source
-                                                    .additionalDataFormItems,
+                                                    .additionalSourceAppSpecificFormItems,
                                                 defaultValues: app != null
                                                     ? app.app.additionalData
                                                     : source
-                                                        .additionalDataDefaults);
+                                                        .additionalSourceAppSpecificDefaults);
                                           }).then((values) {
                                         if (app != null && values != null) {
                                           var changedApp = app.app;
@@ -234,8 +236,12 @@ class _AppPageState extends State<AppPage> {
                                       }
                                     : null,
                                 child: Text(app?.app.installedVersion == null
+                                    ? app?.app.trackOnly == false
                                         ? 'Install'
-                                    : 'Update'))),
+                                        : 'Mark Installed'
+                                    : app?.app.trackOnly == false
+                                        ? 'Update'
+                                        : 'Mark Updated'))),
                         const SizedBox(width: 16.0),
                         ElevatedButton(
                           onPressed: app?.downloadProgress != null

lib/pages/apps.dart

@@ -135,6 +135,22 @@ class AppsPageState extends State<AppsPage> {
             : selectedApps.map((e) => e.id).contains(element))
         .toList();
 
+    List<String> trackOnlyUpdateIdsAllOrSelected = [];
+    existingUpdateIdsAllOrSelected = existingUpdateIdsAllOrSelected.where((id) {
+      if (appsProvider.apps[id]!.app.trackOnly) {
+        trackOnlyUpdateIdsAllOrSelected.add(id);
+        return false;
+      }
+      return true;
+    }).toList();
+    newInstallIdsAllOrSelected = newInstallIdsAllOrSelected.where((id) {
+      if (appsProvider.apps[id]!.app.trackOnly) {
+        trackOnlyUpdateIdsAllOrSelected.add(id);
+        return false;
+      }
+      return true;
+    }).toList();
+
     if (settingsProvider.pinUpdates) {
       var temp = [];
       sortedApps = sortedApps.where((sa) {
@@ -245,7 +261,7 @@ class AppsPageState extends State<AppsPage> {
                             children: [
                               Text(appsProvider.areDownloadsRunning()
                                   ? 'Please Wait...'
-                                  : 'Update Available'),
+                                  : 'Update Available${sortedApps[index].app.trackOnly ? ' (Est.)' : ''}'),
                               SourceProvider()
                                           .getSource(sortedApps[index].app.url)
                                           .changeLogPageFromStandardUrl(
@@ -276,8 +292,7 @@ class AppsPageState extends State<AppsPage> {
                             child: SizedBox(
                                 width: 80,
                                 child: Text(
-                                  sortedApps[index].app.installedVersion ??
+                                  '${sortedApps[index].app.installedVersion ?? 'Not Installed'} ${sortedApps[index].app.trackOnly == true ? '(Estimate)' : ''}',
-                                      'Not Installed',
                                   overflow: TextOverflow.fade,
                                   textAlign: TextAlign.end,
                                 )))),
@@ -349,50 +364,70 @@ class AppsPageState extends State<AppsPage> {
                     visualDensity: VisualDensity.compact,
                     onPressed: appsProvider.areDownloadsRunning() ||
                             (existingUpdateIdsAllOrSelected.isEmpty &&
-                                newInstallIdsAllOrSelected.isEmpty)
+                                newInstallIdsAllOrSelected.isEmpty &&
+                                trackOnlyUpdateIdsAllOrSelected.isEmpty)
                         ? null
                         : () {
                             HapticFeedback.heavyImpact();
-                            List<List<GeneratedFormItem>> formInputs = [];
+                            List<GeneratedFormItem> formInputs = [];
-                            if (existingUpdateIdsAllOrSelected.isNotEmpty &&
+                            List<String> defaultValues = [];
-                                newInstallIdsAllOrSelected.isNotEmpty) {
+                            if (existingUpdateIdsAllOrSelected.isNotEmpty) {
-                              formInputs.add([
+                              formInputs.add(GeneratedFormItem(
-                                GeneratedFormItem(
                                   label:
                                       'Update ${existingUpdateIdsAllOrSelected.length} App${existingUpdateIdsAllOrSelected.length == 1 ? '' : 's'}',
-                                    type: FormItemType.bool)
+                                  type: FormItemType.bool,
-                              ]);
+                                  key: 'updates'));
-                              formInputs.add([
+                              defaultValues.add('true');
-                                GeneratedFormItem(
+                            }
+                            if (newInstallIdsAllOrSelected.isNotEmpty) {
+                              formInputs.add(GeneratedFormItem(
                                   label:
                                       'Install ${newInstallIdsAllOrSelected.length} new App${newInstallIdsAllOrSelected.length == 1 ? '' : 's'}',
-                                    type: FormItemType.bool)
+                                  type: FormItemType.bool,
-                              ]);
+                                  key: 'installs'));
+                              defaultValues
+                                  .add(defaultValues.isEmpty ? 'true' : '');
+                            }
+                            if (trackOnlyUpdateIdsAllOrSelected.isNotEmpty) {
+                              formInputs.add(GeneratedFormItem(
+                                  label:
+                                      'Mark ${trackOnlyUpdateIdsAllOrSelected.length} Track-Only\nApp${trackOnlyUpdateIdsAllOrSelected.length == 1 ? '' : 's'} as Updated',
+                                  type: FormItemType.bool,
+                                  key: 'trackonlies'));
+                              defaultValues
+                                  .add(defaultValues.isEmpty ? 'true' : '');
                             }
                             showDialog<List<String>?>(
                                 context: context,
                                 builder: (BuildContext ctx) {
+                                  var totalApps = existingUpdateIdsAllOrSelected
+                                          .length +
+                                      newInstallIdsAllOrSelected.length +
+                                      trackOnlyUpdateIdsAllOrSelected.length;
                                   return GeneratedFormModal(
                                     title:
-                                        'Install${selectedApps.isEmpty ? ' ' : ' Selected '}Apps?',
+                                        'Change $totalApps App${totalApps == 1 ? '' : 's'}',
-                                    message:
+                                    items: formInputs.map((e) => [e]).toList(),
-                                        '${existingUpdateIdsAllOrSelected.length} update${existingUpdateIdsAllOrSelected.length == 1 ? '' : 's'} and ${newInstallIdsAllOrSelected.length} new install${newInstallIdsAllOrSelected.length == 1 ? '' : 's'}.',
+                                    defaultValues: defaultValues,
-                                    items: formInputs,
-                                    defaultValues: [
-                                      'true',
-                                      existingUpdateIdsAllOrSelected.isEmpty
-                                          ? 'true'
-                                          : ''
-                                    ],
                                     initValid: true,
                                   );
                                 }).then((values) {
                               if (values != null) {
                                 if (values.isEmpty) {
-                                  values = ['true', 'true'];
+                                  values = defaultValues;
                                 }
-                                bool shouldInstallUpdates = values[0] == 'true';
+                                bool shouldInstallUpdates =
-                                bool shouldInstallNew = values[1] == 'true';
+                                    findGeneratedFormValueByKey(
+                                            formInputs, values, 'updates') ==
+                                        'true';
+                                bool shouldInstallNew =
+                                    findGeneratedFormValueByKey(
+                                            formInputs, values, 'installs') ==
+                                        'true';
+                                bool shouldMarkTrackOnlies =
+                                    findGeneratedFormValueByKey(formInputs,
+                                            values, 'trackonlies') ==
+                                        'true';
                                 settingsProvider
                                     .getInstallPermission()
                                     .then((_) {
@@ -405,6 +440,10 @@ class AppsPageState extends State<AppsPage> {
                                     toInstall
                                         .addAll(newInstallIdsAllOrSelected);
                                   }
+                                  if (shouldMarkTrackOnlies) {
+                                    toInstall.addAll(
+                                        trackOnlyUpdateIdsAllOrSelected);
+                                  }
                                   appsProvider
                                       .downloadAndInstallLatestApps(
                                           toInstall, context)

lib/pages/import_export.dart

@@ -42,7 +42,7 @@ class _ImportExportPageState extends State<ImportExportPage> {
 
     Future<List<List<String>>> addApps(List<String> urls) async {
       await settingsProvider.getInstallPermission();
-      List<dynamic> results = await sourceProvider.getApps(urls,
+      List<dynamic> results = await sourceProvider.getAppsByURLNaive(urls,
           ignoreUrls: appsProvider.apps.values.map((e) => e.app.url).toList());
       List<App> apps = results[0];
       Map<String, dynamic> errorsMap = results[1];

lib/pages/settings.dart

@@ -139,18 +139,21 @@ class _SettingsPageState extends State<SettingsPage> {
         });
 
     var sourceSpecificFields = sourceProvider.sources.map((e) {
-      if (e.moreSourceSettingsFormItems.isNotEmpty) {
+      if (e.additionalSourceSpecificSettingFormItems.isNotEmpty) {
         return GeneratedForm(
-            items: e.moreSourceSettingsFormItems.map((e) => [e]).toList(),
+            items: e.additionalSourceSpecificSettingFormItems
+                .map((e) => [e])
+                .toList(),
             onValueChanges: (values, valid, isBuilding) {
               if (valid) {
                 for (var i = 0; i < values.length; i++) {
                   settingsProvider.setSettingString(
-                      e.moreSourceSettingsFormItems[i].id, values[i]);
+                      e.additionalSourceSpecificSettingFormItems[i].id,
+                      values[i]);
                 }
               }
             },
-            defaultValues: e.moreSourceSettingsFormItems.map((e) {
+            defaultValues: e.additionalSourceSpecificSettingFormItems.map((e) {
               return settingsProvider.getSettingString(e.id) ?? '';
             }).toList());
       } else {

lib/providers/apps_provider.dart

@@ -266,6 +266,7 @@ class AppsProvider with ChangeNotifier {
   Future<List<String>> downloadAndInstallLatestApps(
       List<String> appIds, BuildContext? context) async {
     List<String> appsToInstall = [];
+    List<String> trackOnlyAppsToUpdate = [];
     // For all specified Apps, filter out those for which:
     // 1. A URL cannot be picked
     // 2. That cannot be installed silently (IF no buildContext was given for interactive install)
@@ -273,7 +274,10 @@ class AppsProvider with ChangeNotifier {
       if (apps[id] == null) {
         throw ObtainiumError('App not found');
       }
-      String? apkUrl = await confirmApkUrl(apps[id]!.app, context);
+      String? apkUrl;
+      if (!apps[id]!.app.trackOnly) {
+        apkUrl = await confirmApkUrl(apps[id]!.app, context);
+      }
       if (apkUrl != null) {
         int urlInd = apps[id]!.app.apkUrls.indexOf(apkUrl);
         if (urlInd != apps[id]!.app.preferredApkIndex) {
@@ -284,7 +288,16 @@ class AppsProvider with ChangeNotifier {
           appsToInstall.add(id);
         }
       }
+      if (apps[id]!.app.trackOnly) {
+        trackOnlyAppsToUpdate.add(id);
       }
+    }
+    // Mark all specified track-only apps as latest
+    saveApps(trackOnlyAppsToUpdate.map((e) {
+      var a = apps[e]!.app;
+      a.installedVersion = a.latestVersion;
+      return a;
+    }).toList());
     // Download APKs for all Apps to be installed
     MultiAppMultiError errors = MultiAppMultiError();
     List<DownloadedApk?> downloadedFiles =
@@ -391,7 +404,9 @@ class AppsProvider with ChangeNotifier {
       return null; // Can't correct in the background isolate
     }
     var modded = false;
-    if (installedInfo == null && app.installedVersion != null) {
+    if (installedInfo == null &&
+        app.installedVersion != null &&
+        !app.trackOnly) {
       app.installedVersion = null;
       modded = true;
     }
@@ -445,8 +460,7 @@ class AppsProvider with ChangeNotifier {
       var info = await getInstalledInfo(newApps[i].id);
       try {
         sp.getSource(newApps[i].url);
-        apps.putIfAbsent(
+        apps[newApps[i].id] = AppInMemory(newApps[i], null, info);
-            newApps[i].id, () => AppInMemory(newApps[i], null, info));
       } catch (e) {
         errors.add([newApps[i].id, newApps[i].name, e.toString()]);
       }
@@ -512,8 +526,9 @@ class AppsProvider with ChangeNotifier {
         currentApp.additionalData,
         name: currentApp.name,
         id: currentApp.id,
-        pinned: currentApp.pinned);
+        pinned: currentApp.pinned,
-    newApp.installedVersion = currentApp.installedVersion;
+        trackOnly: currentApp.trackOnly,
+        installedVersion: currentApp.installedVersion);
     if (currentApp.preferredApkIndex < newApp.apkUrls.length) {
       newApp.preferredApkIndex = currentApp.preferredApkIndex;
     }

lib/providers/source_provider.dart

@@ -42,6 +42,7 @@ class App {
   late List<String> additionalData;
   late DateTime? lastUpdateCheck;
   bool pinned = false;
+  bool trackOnly = false;
   App(
       this.id,
       this.url,
@@ -53,7 +54,8 @@ class App {
       this.preferredApkIndex,
       this.additionalData,
       this.lastUpdateCheck,
-      this.pinned);
+      this.pinned,
+      this.trackOnly);
 
   @override
   String toString() {
@@ -74,12 +76,15 @@ class App {
           : List<String>.from(jsonDecode(json['apkUrls'])),
       json['preferredApkIndex'] == null ? 0 : json['preferredApkIndex'] as int,
       json['additionalData'] == null
-          ? SourceProvider().getSource(json['url']).additionalDataDefaults
+          ? SourceProvider()
+              .getSource(json['url'])
+              .additionalSourceAppSpecificDefaults
           : List<String>.from(jsonDecode(json['additionalData'])),
       json['lastUpdateCheck'] == null
           ? null
           : DateTime.fromMicrosecondsSinceEpoch(json['lastUpdateCheck']),
-      json['pinned'] ?? false);
+      json['pinned'] ?? false,
+      json['trackOnly'] ?? false);
 
   Map<String, dynamic> toJson() => {
         'id': id,
@@ -92,7 +97,8 @@ class App {
         'preferredApkIndex': preferredApkIndex,
         'additionalData': jsonEncode(additionalData),
         'lastUpdateCheck': lastUpdateCheck?.microsecondsSinceEpoch,
-        'pinned': pinned
+        'pinned': pinned,
+        'trackOnly': trackOnly
       };
 }
 
@@ -135,6 +141,7 @@ List<String> getLinksFromParsedHTML(
 
 class AppSource {
   late String host;
+  bool enforceTrackOnly = false;
   String standardizeURL(String url) {
     throw NotImplementedError();
   }
@@ -148,9 +155,22 @@ class AppSource {
     throw NotImplementedError();
   }
 
-  List<List<GeneratedFormItem>> additionalDataFormItems = [];
+  // Different Sources may need different kinds of additional data for Apps
-  List<String> additionalDataDefaults = [];
+  List<List<GeneratedFormItem>> additionalSourceAppSpecificFormItems = [];
-  List<GeneratedFormItem> moreSourceSettingsFormItems = [];
+  List<String> additionalSourceAppSpecificDefaults = [];
+
+  // Some additional data may be needed for Apps regardless of Source
+  final List<GeneratedFormItem> additionalAppSpecificSourceAgnosticFormItems = [
+    GeneratedFormItem(
+        label: 'Track-Only',
+        type: FormItemType.bool,
+        key: 'trackOnlyFormItemKey')
+  ];
+  final List<String> additionalAppSpecificSourceAgnosticDefaults = [''];
+
+  // Some Sources may have additional settings at the Source level (not specific to Apps) - these use SettingsProvider
+  List<GeneratedFormItem> additionalSourceSpecificSettingFormItems = [];
+
   String? changeLogPageFromStandardUrl(String standardUrl) {
     throw NotImplementedError();
   }
@@ -211,7 +231,7 @@ class SourceProvider {
   }
 
   bool ifSourceAppsRequireAdditionalData(AppSource source) {
-    for (var row in source.additionalDataFormItems) {
+    for (var row in source.additionalSourceAppSpecificFormItems) {
       for (var element in row) {
         if (element.required) {
           return true;
@@ -238,11 +258,19 @@ class SourceProvider {
   }
 
   Future<App> getApp(AppSource source, String url, List<String> additionalData,
-      {String name = '', String? id, bool pinned = false}) async {
+      {String name = '',
+      String? id,
+      bool pinned = false,
+      bool trackOnly = false,
+      String? installedVersion}) async {
     String standardUrl = source.standardizeURL(preStandardizeUrl(url));
     AppNames names = source.getAppNames(standardUrl);
     APKDetails apk =
         await source.getLatestAPKDetails(standardUrl, additionalData);
+    if (apk.apkUrls.isEmpty && !trackOnly) {
+      throw NoAPKError();
+    }
+    String apkVersion = apk.version.replaceAll('/', '-');
     return App(
         id ??
             source.tryInferringAppId(standardUrl) ??
@@ -252,24 +280,26 @@ class SourceProvider {
         name.trim().isNotEmpty
             ? name
             : names.name[0].toUpperCase() + names.name.substring(1),
-        null,
+        installedVersion,
-        apk.version.replaceAll('/', '-'),
+        apkVersion,
         apk.apkUrls,
         apk.apkUrls.length - 1,
         additionalData,
         DateTime.now(),
-        pinned);
+        pinned,
+        trackOnly);
   }
 
   // Returns errors in [results, errors] instead of throwing them
-  Future<List<dynamic>> getApps(List<String> urls,
+  Future<List<dynamic>> getAppsByURLNaive(List<String> urls,
       {List<String> ignoreUrls = const []}) async {
     List<App> apps = [];
     Map<String, dynamic> errors = {};
     for (var url in urls.where((element) => !ignoreUrls.contains(element))) {
       try {
         var source = getSource(url);
-        apps.add(await getApp(source, url, source.additionalDataDefaults));
+        apps.add(await getApp(
+            source, url, source.additionalSourceAppSpecificDefaults));
       } catch (e) {
         errors.addAll(<String, dynamic>{url: e});
       }