On devices running Android 8.0 (API level 26) and higher, companion device
pairing performs a Bluetooth or Wi-Fi scan of nearby devices on behalf of your
app without requiring the
ACCESS_FINE_LOCATION
permission. This helps maximize user privacy protections. After the device is
paired, the device can leverage the
REQUEST_COMPANION_RUN_IN_BACKGROUND
and
REQUEST_COMPANION_USE_DATA_IN_BACKGROUND
permissions to start the app from the background. Use this method to perform the
initial configuration of the companion device, such as a BLE-capable smart
watch. In addition, companion device pairing requires Location Services to be
enabled.
Companion device pairing doesn't create connections on its own. Bluetooth and Wi-Fi connectivity APIs establish connections. Nor does companion device pairing enable continuous scanning.
A user can select a device from a list and grant it permission to access an app.
These permissions are revoked if you uninstall the app or call
disassociate().
An app is responsible for clearing its own associations if the user no longer
needs them, such as when they log out or remove bonded devices.
Implement companion device pairing
To make and manage a connection to a companion device, use the
CompanionDeviceManager.
This section explains how to customize your pairing request dialog when you pair
your app with companion devices over Bluetooth, BLE, and Wi-Fi.
Specify companion devices
The following code sample shows how to add the
<uses-feature> flag to a
manifest file. This tells the system that your app intends to set up companion
devices.
<uses-feature android:name="android.software.companion_device_setup"/>
List devices by type
You can display all possible companion devices available that match the filter
you provide, or limit the display to a single option (shown in figure 1). You
configure this by creating a filter that specifies what types of devices your
app is looking for or by setting
setSingleDevice()
to true (shown in figure 2).
To apply a filter to the list of companion devices that appears in your request
dialog, check if Bluetooth is on
or check if Wi-Fi is
on.
After a connection is enabled, you can add a
DeviceFilter. The following
subclasses of DeviceFilter specify the types of devices your app can associate
with based on a connection type:
All three subclasses have builders that streamline the configuration of filters.
In the following example, a device scans for a Bluetooth device with a
BluetoothDeviceFilter.
Kotlin
val deviceFilter: BluetoothDeviceFilter = BluetoothDeviceFilter.Builder()
// Match only Bluetooth devices whose name matches the pattern.
.setNamePattern(Pattern.compile("My device"))
// Match only Bluetooth devices whose service UUID matches this pattern.
.addServiceUuid(ParcelUuid(UUID(0x123abcL, -1L)), null)
.build()
Java
BluetoothDeviceFilter deviceFilter = new BluetoothDeviceFilter.Builder()
// Match only Bluetooth devices whose name matches the pattern.
.setNamePattern(Pattern.compile("My device"))
// Match only Bluetooth devices whose service UUID matches this pattern.
.addServiceUuid(new ParcelUuid(new UUID(0x123abcL, -1L)), null)
.build();
Set a DeviceFilter to an
AssociationRequest so the
device manager can determine what type of device to seek.
Kotlin
val pairingRequest: AssociationRequest = AssociationRequest.Builder()
// Find only devices that match this request filter.
.addDeviceFilter(deviceFilter)
// Stop scanning as soon as one device matching the filter is found.
.setSingleDevice(true)
.build()
Java
AssociationRequest pairingRequest = new AssociationRequest.Builder()
// Find only devices that match this request filter.
.addDeviceFilter(deviceFilter)
// Stop scanning as soon as one device matching the filter is found.
.setSingleDevice(true)
.build();
After you initialize an AssociationRequest, run the
associate()
function on the CompanionDeviceManager. The associate() function takes in
pairing request object and callback. Callbacks indicate when an app locates a
device and it's ready to launch a dialog box for the user to input their choice.
If an app doesn't find any devices, the callback returns an error message.
On devices running Android 13 (API level 33) and higher:
Kotlin
val deviceManager =
requireContext().getSystemService(Context.COMPANION_DEVICE_SERVICE)
val executor: Executor = Executor { it.run() }
deviceManager.associate(pairingRequest,
executor,
object : CompanionDeviceManager.Callback() {
// Called when a device is found. Launch the IntentSender so the user
// can select the device they want to pair with.
override fun onAssociationPending(intentSender: IntentSender) {
intentSender?.let {
startIntentSenderForResult(it, SELECT_DEVICE_REQUEST_CODE, null, 0, 0, 0)
}
}
override fun onAssociationCreated(associationInfo: AssociationInfo) {
// The association is created.
}
override fun onFailure(errorMessage: CharSequence?) {
// Handle the failure.
}
})
Java
CompanionDeviceManager deviceManager =
(CompanionDeviceManager) getSystemService(Context.COMPANION_DEVICE_SERVICE);
Executor executor = new Executor() {
@Override
public void execute(Runnable runnable) {
runnable.run();
}
};
deviceManager.associate(pairingRequest, new CompanionDeviceManager.Callback() {
executor,
// Called when a device is found. Launch the IntentSender so the user can
// select the device they want to pair with.
@Override
public void onDeviceFound(IntentSender chooserLauncher) {
try {
startIntentSenderForResult(
chooserLauncher, SELECT_DEVICE_REQUEST_CODE, null, 0, 0, 0
);
} catch (IntentSender.SendIntentException e) {
Log.e("MainActivity", "Failed to send intent");
}
}
@Override
public void onAssociationCreated(AssociationInfo associationInfo) {
// The association is created.
}
@Override
public void onFailure(CharSequence errorMessage) {
// Handle the failure.
});
On devices running Android 12L (API level 32) and below (deprecated):
Kotlin
val deviceManager =
requireContext().getSystemService(Context.COMPANION_DEVICE_SERVICE)
deviceManager.associate(pairingRequest,
object : CompanionDeviceManager.Callback() {
// Called when a device is found. Launch the IntentSender so the user
// can select the device they want to pair with.
override fun onDeviceFound(chooserLauncher: IntentSender) {
startIntentSenderForResult(chooserLauncher,
SELECT_DEVICE_REQUEST_CODE, null, 0, 0, 0)
}
override fun onFailure(error: CharSequence?) {
// Handle the failure.
}
}, null)
Java
CompanionDeviceManager deviceManager =
(CompanionDeviceManager) getSystemService(Context.COMPANION_DEVICE_SERVICE);
deviceManager.associate(pairingRequest, new CompanionDeviceManager.Callback() {
// Called when a device is found. Launch the IntentSender so the user can
// select the device they want to pair with.
@Override
public void onDeviceFound(IntentSender chooserLauncher) {
try {
startIntentSenderForResult(
chooserLauncher, SELECT_DEVICE_REQUEST_CODE, null, 0, 0, 0
);
} catch (IntentSender.SendIntentException e) {
Log.e("MainActivity", "Failed to send intent");
}
}
@Override
public void onFailure(CharSequence error) {
// Handle the failure.
}
}, null);
To empower users to select what type of devices they want to connect to, start a
preferences activity with the intentSender parameter in the onAssociationPending() function. The results of this action are sent back to the fragment in the
onActivityResult()
function of your preferences activity. This updates you when the user makes a
selection based on the result. You can then access the selected device. When a
user selects a Bluetooth device, the result sent is a
BluetoothDevice object.
Similarly, when the onAssociationPending() function detects that a user selects a
Bluetooth LE device, expect an
android.bluetooth.le.ScanResult
object. For Wi-Fi devices, expect a
android.net.wifi.ScanResult object.
Kotlin
override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
when (requestCode) {
SELECT_DEVICE_REQUEST_CODE -> when(resultCode) {
Activity.RESULT_OK -> {
// The user chose to pair the app with a Bluetooth device.
val deviceToPair: BluetoothDevice? =
data?.getParcelableExtra(CompanionDeviceManager.EXTRA_DEVICE)
deviceToPair?.let { device ->
device.createBond()
// Continue to interact with the paired device.
}
}
}
else -> super.onActivityResult(requestCode, resultCode, data)
}
}
Java
@Override
protected void onActivityResult(int requestCode, int resultCode, @Nullable Intent data) {
if (resultCode != Activity.RESULT_OK) {
return;
}
if (requestCode == SELECT_DEVICE_REQUEST_CODE && data != null) {
BluetoothDevice deviceToPair =
data.getParcelableExtra(CompanionDeviceManager.EXTRA_DEVICE);
if (deviceToPair != null) {
deviceToPair.createBond();
// Continue to interact with the paired device.
}
} else {
super.onActivityResult(requestCode, resultCode, data);
}
}
To implement companion device pairing with filters that can specify devices and list them by type, see the following examples:
On devices running Android 13 (API level 33) and higher:
Kotlin
private const val SELECT_DEVICE_REQUEST_CODE = 0
class MainActivity : AppCompatActivity() {
private val deviceManager: CompanionDeviceManager by lazy {
getSystemService(Context.COMPANION_DEVICE_SERVICE) as CompanionDeviceManager
}
val mBluetoothAdapter: BluetoothAdapter by lazy {
val java = BluetoothManager::class.java
getSystemService(java)!!.adapter }
val executor: Executor = Executor { it.run() }
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
// To skip filters based on names and supported feature flags (UUIDs),
// omit calls to setNamePattern() and addServiceUuid()
// respectively, as shown in the following Bluetooth example.
val deviceFilter: BluetoothDeviceFilter = BluetoothDeviceFilter.Builder()
.setNamePattern(Pattern.compile("My device"))
.addServiceUuid(ParcelUuid(UUID(0x123abcL, -1L)), null)
.build()
// The argument provided in setSingleDevice() determines whether a single
// device name or a list of them appears.
val pairingRequest: AssociationRequest = AssociationRequest.Builder()
.addDeviceFilter(deviceFilter)
.setSingleDevice(true)
.build()
// When the app tries to pair with a Bluetooth device, show the
// corresponding dialog box to the user.
deviceManager.associate(pairingRequest,
executor,
object : CompanionDeviceManager.Callback() {
// Called when a device is found. Launch the IntentSender so the user
// can select the device they want to pair with.
override fun onAssociationPending(intentSender: IntentSender) {
intentSender?.let {
startIntentSenderForResult(it, SELECT_DEVICE_REQUEST_CODE, null, 0, 0, 0)
}
}
override fun onAssociationCreated(associationInfo: AssociationInfo) {
// AssociationInfo object is created and get association id and the
// macAddress.
var associationId: int = associationInfo.id
var macAddress: MacAddress = associationInfo.deviceMacAddress
}
override fun onFailure(errorMessage: CharSequence?) {
// Handle the failure.
}
)
override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
when (requestCode) {
SELECT_DEVICE_REQUEST_CODE -> when(resultCode) {
Activity.RESULT_OK -> {
// The user chose to pair the app with a Bluetooth device.
val deviceToPair: BluetoothDevice? =
data?.getParcelableExtra(CompanionDeviceManager.EXTRA_DEVICE)
deviceToPair?.let { device ->
device.createBond()
// Maintain continuous interaction with a paired device.
}
}
}
else -> super.onActivityResult(requestCode, resultCode, data)
}
}
}
Java
class MainActivityJava extends AppCompatActivity {
private static final int SELECT_DEVICE_REQUEST_CODE = 0;
Executor executor = new Executor() {
@Override
public void execute(Runnable runnable) {
runnable.run();
}
};
@Override
protected void onCreate(@Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
CompanionDeviceManager deviceManager =
(CompanionDeviceManager) getSystemService(
Context.COMPANION_DEVICE_SERVICE
);
// To skip filtering based on name and supported feature flags,
// do not include calls to setNamePattern() and addServiceUuid(),
// respectively. This example uses Bluetooth.
BluetoothDeviceFilter deviceFilter =
new BluetoothDeviceFilter.Builder()
.setNamePattern(Pattern.compile("My device"))
.addServiceUuid(
new ParcelUuid(new UUID(0x123abcL, -1L)), null
)
.build();
// The argument provided in setSingleDevice() determines whether a single
// device name or a list of device names is presented to the user as
// pairing options.
AssociationRequest pairingRequest = new AssociationRequest.Builder()
.addDeviceFilter(deviceFilter)
.setSingleDevice(true)
.build();
// When the app tries to pair with the Bluetooth device, show the
// appropriate pairing request dialog to the user.
deviceManager.associate(pairingRequest, new CompanionDeviceManager.Callback() {
executor,
// Called when a device is found. Launch the IntentSender so the user can
// select the device they want to pair with.
@Override
public void onDeviceFound(IntentSender chooserLauncher) {
try {
startIntentSenderForResult(
chooserLauncher, SELECT_DEVICE_REQUEST_CODE, null, 0, 0, 0
);
} catch (IntentSender.SendIntentException e) {
Log.e("MainActivity", "Failed to send intent");
}
}
@Override
public void onAssociationCreated(AssociationInfo associationInfo) {
// AssociationInfo object is created and get association id and the
// macAddress.
int associationId = associationInfo.getId();
MacAddress macAddress = associationInfo.getDeviceMacAddress();
}
@Override
public void onFailure(CharSequence errorMessage) {
// Handle the failure.
});
}
@Override
protected void onActivityResult(int requestCode, int resultCode, @Nullable Intent data) {
if (resultCode != Activity.RESULT_OK) {
return;
}
if (requestCode == SELECT_DEVICE_REQUEST_CODE) {
if (resultCode == Activity.RESULT_OK && data != null) {
BluetoothDevice deviceToPair = data.getParcelableExtra(
CompanionDeviceManager.EXTRA_DEVICE
);
if (deviceToPair != null) {
deviceToPair.createBond();
// ... Continue interacting with the paired device.
}
}
} else {
super.onActivityResult(requestCode, resultCode, data);
}
}
}
On devices running Android 12L (API level 32) and below (deprecated):
Kotlin
private const val SELECT_DEVICE_REQUEST_CODE = 0
class MainActivity : AppCompatActivity() {
private val deviceManager: CompanionDeviceManager by lazy {
getSystemService(Context.COMPANION_DEVICE_SERVICE) as CompanionDeviceManager
}
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
// To skip filters based on names and supported feature flags (UUIDs),
// omit calls to setNamePattern() and addServiceUuid()
// respectively, as shown in the following Bluetooth example.
val deviceFilter: BluetoothDeviceFilter = BluetoothDeviceFilter.Builder()
.setNamePattern(Pattern.compile("My device"))
.addServiceUuid(ParcelUuid(UUID(0x123abcL, -1L)), null)
.build()
// The argument provided in setSingleDevice() determines whether a single
// device name or a list of them appears.
val pairingRequest: AssociationRequest = AssociationRequest.Builder()
.addDeviceFilter(deviceFilter)
.setSingleDevice(true)
.build()
// When the app tries to pair with a Bluetooth device, show the
// corresponding dialog box to the user.
deviceManager.associate(pairingRequest,
object : CompanionDeviceManager.Callback() {
override fun onDeviceFound(chooserLauncher: IntentSender) {
startIntentSenderForResult(chooserLauncher,
SELECT_DEVICE_REQUEST_CODE, null, 0, 0, 0)
}
override fun onFailure(error: CharSequence?) {
// Handle the failure.
}
}, null)
}
override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
when (requestCode) {
SELECT_DEVICE_REQUEST_CODE -> when(resultCode) {
Activity.RESULT_OK -> {
// The user chose to pair the app with a Bluetooth device.
val deviceToPair: BluetoothDevice? =
data?.getParcelableExtra(CompanionDeviceManager.EXTRA_DEVICE)
deviceToPair?.let { device ->
device.createBond()
// Maintain continuous interaction with a paired device.
}
}
}
else -> super.onActivityResult(requestCode, resultCode, data)
}
}
}
Java
class MainActivityJava extends AppCompatActivity {
private static final int SELECT_DEVICE_REQUEST_CODE = 0;
@Override
protected void onCreate(@Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
CompanionDeviceManager deviceManager =
(CompanionDeviceManager) getSystemService(
Context.COMPANION_DEVICE_SERVICE
);
// To skip filtering based on name and supported feature flags,
// don't include calls to setNamePattern() and addServiceUuid(),
// respectively. This example uses Bluetooth.
BluetoothDeviceFilter deviceFilter =
new BluetoothDeviceFilter.Builder()
.setNamePattern(Pattern.compile("My device"))
.addServiceUuid(
new ParcelUuid(new UUID(0x123abcL, -1L)), null
)
.build();
// The argument provided in setSingleDevice() determines whether a single
// device name or a list of device names is presented to the user as
// pairing options.
AssociationRequest pairingRequest = new AssociationRequest.Builder()
.addDeviceFilter(deviceFilter)
.setSingleDevice(true)
.build();
// When the app tries to pair with the Bluetooth device, show the
// appropriate pairing request dialog to the user.
deviceManager.associate(pairingRequest,
new CompanionDeviceManager.Callback() {
@Override
public void onDeviceFound(IntentSender chooserLauncher) {
try {
startIntentSenderForResult(chooserLauncher,
SELECT_DEVICE_REQUEST_CODE, null, 0, 0, 0);
} catch (IntentSender.SendIntentException e) {
// failed to send the intent
}
}
@Override
public void onFailure(CharSequence error) {
// handle failure to find the companion device
}
}, null);
}
@Override
protected void onActivityResult(int requestCode, int resultCode, @Nullable Intent data) {
if (requestCode == SELECT_DEVICE_REQUEST_CODE) {
if (resultCode == Activity.RESULT_OK && data != null) {
BluetoothDevice deviceToPair = data.getParcelableExtra(
CompanionDeviceManager.EXTRA_DEVICE
);
if (deviceToPair != null) {
deviceToPair.createBond();
// ... Continue interacting with the paired device.
}
}
} else {
super.onActivityResult(requestCode, resultCode, data);
}
}
}
Companion device profiles
Partner apps on Android 12 (API level 31) and higher can use companion device profiles when connecting to a watch. For more information, see the guide to requesting permissions on Wear OS.
Keep companion apps awake
On Android 12 (API level 31) and higher, you can use additional APIs help your companion app stay running while a companion device is within range. These APIs let you do the following:
Wake your app when a companion device is within range.
For details, see
CompanionDeviceManager.startObservingDevicePresence().Guarantee that an app process will continue running so long as the companion device stays within range.
For details, see
CompanionDeviceService.onDeviceAppeared().