# Check native app availability before offering a launch

Canonical HTML: https://p-hatan.com/deeplink-x/use-cases/installed-apps/

DeeplinkX 1.5.8.

When your workflow specifically requires a native app, check a known provider's availability before enabling its launch action. This recipe checks a configured list; it does not enumerate all applications installed on a device.

## Reusable Flutter example

```dart
import 'package:deeplink_x/deeplink_x.dart';

Future<bool> openInstalledTelegram() async {
  final deeplinkX = DeeplinkX();
  final app = Telegram();

  if (!app.supportedPlatforms.contains(deeplinkX.currentPlatform)) {
    return false;
  }
  if (!await deeplinkX.isAppInstalled(app)) {
    return false;
  }

  return deeplinkX.launchApp(app, disableFallback: true);
}
```

For a UI list, keep unsupported and not-installed as separate states even though this small helper returns `false` for both.

## Current example behavior

`InstalledAppsPage` builds groups for Apps, Maps, and Stores. It checks entries concurrently with `Future.wait`, supports a refresh button and pull-to-refresh, and displays four states:

| State | Meaning in this sample |
| --- | --- |
| Checking | The availability request is pending. |
| Installed | The configured native check returned true. |
| Not installed | The app supports the current platform but its availability check returned false. |
| Unsupported | The app's declared native platform list excludes this platform. |

Only installed rows can be tapped. Launch uses `launchApp(app, disableFallback: true)`, so a web page or store must not be treated as satisfying this native-only interaction.

The sample screen lists **37 apps/maps and seven stores**. The full app catalog also includes ChatGPT, Netflix, Temu, Snapchat, and CapCut. TomTom GO Expert is experimental.

## Configuration and limits

- Installation detection depends on target platform, declared supported platforms, Android package visibility, iOS scheme queries, and provider metadata. Show unavailable or unsupported status when detection cannot find a native handler.
- Use the [Android visibility declarations](https://github.com/DeepLinkX/DeeplinkX/blob/00d9d2c7c1affe4e2ee459a01afeba82a1480eac/example/android/app/src/main/AndroidManifest.xml), [iOS schemes](https://github.com/DeepLinkX/DeeplinkX/blob/00d9d2c7c1affe4e2ee459a01afeba82a1480eac/example/ios/Runner/Info.plist), and each provider's setup documentation.
- The implementation checks Android package names, macOS bundle identifiers, or configured schemes according to the platform. See [`LauncherUtil.isAppInstalled`](https://github.com/DeepLinkX/DeeplinkX/blob/00d9d2c7c1affe4e2ee459a01afeba82a1480eac/lib/src/utils/launcher_util.dart).
- A successful launch Boolean describes handoff, not completion of a downstream task. Native availability can also change between check and tap.

## UI behavior

- Unsupported entries do not run installation checks and show a distinct status.
- A configured installed app is enabled; missing and unsupported entries remain disabled.
- Tapping an installed entry calls `launchApp` with fallback disabled.
- Refresh resets and recomputes the configured inventory; pending launch taps cannot overlap.
- The hub does not advertise this screen as full device app enumeration or as the exhaustive package catalog.

## Source code

- [InstalledAppsPage, `_buildItems`, `_refresh`, `_launch`](https://github.com/DeepLinkX/DeeplinkX/blob/00d9d2c7c1affe4e2ee459a01afeba82a1480eac/example/lib/use_cases/installed_apps_page.dart)
- [Platform checks](https://github.com/DeepLinkX/DeeplinkX/blob/00d9d2c7c1affe4e2ee459a01afeba82a1480eac/lib/src/utils/launcher_util.dart)
- [Native app launch behavior](https://github.com/DeepLinkX/DeeplinkX/blob/00d9d2c7c1affe4e2ee459a01afeba82a1480eac/lib/src/core/deeplink_x.dart)
- [Main catalog](https://github.com/DeepLinkX/DeeplinkX/blob/00d9d2c7c1affe4e2ee459a01afeba82a1480eac/example/lib/catalog/catalog.dart)

[All use cases](/deeplink-x/use-cases/) · [Map provider selection](/deeplink-x/use-cases/map-selector/) · [Fallback policies](/deeplink-x/use-cases/fallback-playground/)