> ## Documentation Index > Fetch the complete documentation index at: https://docs.mentraglass.com/llms.txt > Use this file to discover all available pages before exploring further. # Troubleshooting > Fix dependency, permission, scan, stream, and React Native build issues. ## Android Dependency Resolution Fails * Confirm your app has `google()` and `mavenCentral()` configured. * Confirm `com.mentraglass:bluetooth-sdk:` matches the SDK version you are integrating. * Confirm Gradle can resolve the companion `com.mentraglass:lc3Lib` artifact transitively. * If a version was just published, Maven Central mirror propagation can lag briefly. Retry after the artifact appears under `https://repo.maven.apache.org/maven2/com/mentraglass/`. * If you are testing an unreleased SDK, publish the SDK and companion artifacts to `mavenLocal()` and include `mavenLocal()` in the app repositories. ## Android Build Fails On Native Libraries * Confirm Android min SDK is at least `28`. * Confirm Java 17 is used by Gradle. * If your app also includes native media or camera dependencies, add `pickFirsts += "**/libc++_shared.so"` under `android.packaging.jniLibs`. * Confirm no app-level packaging rule excludes `libc++_shared.so` or SDK native libraries. * Clean only the app build output first. Do not delete SDK source artifacts unless you are intentionally resetting your workspace. ## iOS Swift Package Resolution Fails Check that your iOS deployment target is at least `15.1`, that the package URL is `https://github.com/Mentra-Community/mentra-bluetooth-sdk-ios.git`, and that Xcode resolves the selected SDK version. If Xcode has stale package state, reset package caches and resolve packages again from Xcode. If your app also uses Firebase with static frameworks, Firebase modular header configuration belongs in your app, not in the Bluetooth SDK. ## React Native Native Module Is Missing * Confirm you are running a development build or production native build. Expo Go cannot load `@mentra/bluetooth-sdk`. * Run `bunx expo prebuild` after adding the SDK plugin to `app.json`. * Confirm `@mentra/bluetooth-sdk` is installed in the app that is being prebuilt. * On iOS, rerun `bunx expo run:ios` after changing native module dependencies. * If you are testing a local SDK package, set `MENTRA_BLUETOOTH_SDK_PACKAGE_PATH` to the same package path you installed with Bun. ## Bluetooth Permission Problems * Android 12+ requires runtime Bluetooth scan/connect permissions. * Android scanning may require location permission or Location services depending on OS version and device policy. * On some Android 12+ devices, scans can start successfully but return zero callbacks until `ACCESS_FINE_LOCATION` is granted. * iOS requires `NSBluetoothAlwaysUsageDescription`. * Microphone/audio features require `RECORD_AUDIO` on Android and `NSMicrophoneUsageDescription` on iOS. ## No Devices Found * Confirm the glasses are charged and in pairing mode. * Confirm OS Bluetooth permissions are granted. * On Android, confirm location permission is granted and device Location services are enabled. * Confirm the selected `DeviceModel` matches the target glasses family. * Stop and restart scanning from the UI instead of scanning indefinitely. * Try pairing from a clean Bluetooth state after forgetting the device. ## Connected But No Events * Subscribe before connecting. * In React Native, render `useMentraBluetooth()` state for connection, battery, Wi-Fi, hotspot, scan, and SDK state. In native Android/iOS apps, log the SDK status objects. * Confirm the hardware feature is available on the connected model. * Watch SDK log callbacks for native diagnostics. ## Connected But SDK Features Fail Bluetooth connection does not confirm that the mobile SDK and glasses software versions match. Each Bluetooth SDK release requires the Mentra Live software release with the same version number. If your app uses SDK `0.1.20`, [install the matching Mentra Live `0.1.20` software](/mentra-live/software-update), then reconnect and check again. Do not debug individual feature failures until the OTA check succeeds with no update remaining. ## Optional Local Stream Preview Does Not Show Video * The local demo cloud is only needed when the starter app's Stream screen has **Use cloud server** enabled. If you are using that optional local stream preview, confirm the local demo cloud or MediaMTX helper is running. * Use the printed LAN URL, not `localhost`, in the example app's RTMP or WebRTC field. * Confirm the glasses, phone, and computer are on a network where local device-to-device traffic is allowed. * Confirm Mentra Live is connected to Wi-Fi before starting the stream. * For RTMP, the native iOS example embeds the derived HLS preview URL while live. You can also open or refresh the printed HLS preview URL on your computer after tapping **Start stream**. * If Docker is running in bridge mode, confirm UDP ports `8890` and `8189` are published. * If the helper picked the wrong network interface, restart it with `python3 examples/local-demo-cloud/server.py --host-ip `. ## React Native Or Expo Apps React Native and Expo apps use the `@mentra/bluetooth-sdk` package and must run as development builds or production native builds. Expo Go cannot load the native SDK. Start from `examples/react-native` for Expo, `examples/android` for bare Android, or `examples/ios` for bare iOS. If Android prebuild succeeds but native linking fails, confirm the generated project includes `:lc3Lib` in `android/settings.gradle`. The SDK plugin adds this module automatically during prebuild. If iOS builds fail with missing Expo adapter symbols, rerun `bunx expo prebuild` so the SDK plugin can configure the Podfile for Expo module registration.