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Supported on Android 6 (minSdk = 23) and above with compileSdk >= 31. For Java on desktop apps, please contact us at

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  1. Ensure your device has Android 6 or higher
  2. Ensure that mavenCentral() is in the project-level build.gradle file like so:
allprojects {    repositories {        mavenCentral()    }}
  1. In the individual module build.gradle file add:
dependencies {  // ...  implementation "live.ditto:ditto:4.1.1"}
  1. Configure your manifest with the following permissions. Ditto's required permissions have changed since Android 13. Refer to Android Platform Permissions for details.

  2. Access the portal to create a new app. Apps created on the portal will automatically sync data between them and also to the Ditto Big Peer. Each app created on the portal has a unique appID which can be seen on your app's settings page once the app has been created. This ID is used in subsequent sections to configure your Ditto instance.

  3. Create your Ditto instance as below. We recommend placing this in your Application.onCreate method. Note that the Context you want to reference here is the Application level Context, rather than whatever Activity you might happen to be instantiating the Ditto instance from initially. This is because you need to ensure that your app is keeping a single Ditto instance alive for the entire lifetime of the application so it's not going out of scope or getting garbage collected.

try {    val androidDependencies = DefaultAndroidDittoDependencies(context)    val identity = DittoIdentity.OnlinePlayground(        androidDependencies,        appId = "REPLACE_ME_WITH_YOUR_APP_ID",        token = "REPLACE_ME_WITH_YOUR_PLAYGROUND_TOKEN"    )    DittoLogger.minimumLogLevel = DittoLogLevel.DEBUG    ditto = Ditto(androidDependencies, identity)    ditto.startSync()} catch (e: DittoError) {    Log.e("Ditto error", e.message!!)}

Android Platform Permissions

The Android operating system restricts access to some device functionality for the sake of user control and privacy. Therefore, to unlock the full capabilities of Ditto, it is essential to configure your app so that it requests all the permissions that it needs.

Then at runtime your app must prompt the user to request certain permissions.

Android Manifest Permissions

The Ditto Android SDK includes a set of permissions that are required to use all the device features necessary to enable sync. The permissions below will be automatically merged into your app's final manifest.

<manifest    xmlns:tools=""    xmlns:android="">
<uses-permission android:name="android.permission.BLUETOOTH"    android:maxSdkVersion="30" /><uses-permission android:name="android.permission.BLUETOOTH_ADMIN"    android:maxSdkVersion="30" /><uses-permission android:name="android.permission.BLUETOOTH_ADVERTISE"    tools:targetApi="s" /><uses-permission android:name="android.permission.BLUETOOTH_CONNECT"    tools:targetApi="s" /><uses-permission android:name="android.permission.BLUETOOTH_SCAN"    android:usesPermissionFlags="neverForLocation"    tools:targetApi="s" /><uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"    android:maxSdkVersion="32" /><uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"    android:maxSdkVersion="30" /><uses-permission android:name="android.permission.INTERNET" /><uses-permission android:name="android.permission.ACCESS_WIFI_STATE" /><uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" /><uses-permission android:name="android.permission.CHANGE_NETWORK_STATE" /><uses-permission android:name="android.permission.CHANGE_WIFI_MULTICAST_STATE" /><uses-permission android:name="android.permission.CHANGE_WIFI_STATE" /><uses-permission android:name="android.permission.NEARBY_WIFI_DEVICES"    android:usesPermissionFlags="neverForLocation"    tools:targetApi="tiramisu" />

The tools:targetApi attribute causes the permission to only be requested on devices running the specified API level or higher. This avoids errors on older OS versions that do not recognize the permission.

The android:maxSdkVersion attribute causes that permission to only be requested on devices running the specified SDK level or lower. This avoids asking for more permissions than Ditto needs, however it will prevent your app from being able to request the permission on devices running a newer OS version. To opt out of this behavior and request the permission on all OS versions, see the following snippet:

Location Permission Override
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"    tools:remove="android:maxSdkVersion" /><uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"    tools:remove="android:maxSdkVersion" />

Note that you may need to add the xmlns:tools="" namespace attribute to your app's root <manifest> tag as shown in the AndroidManifest.xml example above.

This will configure your app's build to ignore the android:maxSdkVersion attribute in our SDK allowing the permission to be requested on any SDK version. This techniquie can be used to tweak any permissions to your liking.

For more details, see the documentation for the Bluetooth and WiFi Aware permissions in the Android Documentation.

Runtime Permissions

Bluetooth LE and WiFi Aware require the user to allow permissions at runtime. Your apps must ensure all required permissions for sync have been requested from the user. The Android Ditto SDK provides a DittoSyncPermissions helper which makes this easy. Call the following in your Activity or Fragment's onCreate method:

The DittoSyncPermissions object requires a Context. You can get the context by invoking getApplicationContext(), getContext(), getBaseContext() or this when in a class that extends from Context, such as the Application, Activity, Service and IntentService classes.

fun checkPermissions() {    val missing = DittoSyncPermissions(this).missingPermissions()    if (missing.isNotEmpty()) {        this.requestPermissions(missing, 0)    }}

Alternatively, requireActivity() is a way to force the code to only work on a Fragment that has a Context.

fun checkPermissions() {    val activity = requireActivity()    val missing = DittoSyncPermissions(activity).missingPermissions()    if (missing.isNotEmpty()) {        activity.requestPermissions(missing, 0)    }}

On Android there may be a noticeable delay between when the user grants location access and when Ditto notices the new permission. For this reason it is recommended to call refreshPermissions() whenever a relevant permission might have changed. This will force an immediate check. If a permission has become available your app can begin syncing as quickly as possible.

override fun onRequestPermissionsResult(    requestCode: Int,    permissions: Array<out String>,    grantResults: IntArray) {    super.onRequestPermissionsResult(requestCode, permissions, grantResults)    // Regardless of the outcome, tell Ditto that permissions maybe changed    ditto?.refreshPermissions()}

For more information about requesting permissions in a user-friendly way refer to Android's documentation: Request App Permissions.