npm install capacitor-branch-deep-links

apply plugin: 'com.android.application'

android {
    defaultConfig {
        // ...
+       multiDexEnabled true
        // ...
    }
}

dependencies {
+    implementation("com.google.android.gms:play-services-ads-identifier:18.0.1") // AAID
+    implementation 'androidx.multidex:multidex:2.0.1' // Only required if your minSDKVersion is 20 or lower
}

<?xml version='1.0' encoding='utf-8'?>
  <resources>
      <!-- ... ->
+     <string name="applink_host">example.app.link</string>
+     <string name="applink_host_alternate">example-alternate.app.link</string>
+     <string name="deeplink_scheme">example</string>
+     <string name="branch_key">key_live_xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx</string>
+     <string name="branch_test_key">key_test_xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx</string>
+     <bool name="branch_test_mode">false</bool>
+     <!-- set above to "true" to use test key -->
  </resources>

package com.example;

+ import android.content.Intent;
import android.os.Bundle;
+ import co.boundstate.BranchDeepLinks;
import com.getcapacitor.BridgeActivity;
import com.getcapacitor.Plugin;
import java.util.ArrayList;
+ import io.branch.referral.Branch;

public class MainActivity extends BridgeActivity {

  @Override
  public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
+   Branch.getInstance().setRequestMetadata("insert_user_id", "value"); // if you need to append partner metadata before initializing Branch
+   registerPlugin(BranchDeepLinks.class);
  }
+
+  @Override
+  protected void onNewIntent(Intent intent) {
+    this.setIntent(intent);
+    super.onNewIntent(intent);
+  }
}

+ package com.example;
+
+ import android.content.Context;
+ import android.os.UserManager;
+ import androidx.multidex.MultiDex;
+ import androidx.multidex.MultiDexApplication;
+ import static android.os.Build.VERSION.SDK_INT;
+ import io.branch.referral.Branch;
+
+ public class CustomApplicationClass extends MultiDexApplication {
+
+   @Override
+   public void onCreate() {
+     super.onCreate();
+
+     // Branch logging for debugging
+     Branch.enableLogging();
+
+     if (SDK_INT >= 24) {
+       UserManager um = getApplicationContext().getSystemService(UserManager.class);
+       if (um == null || !um.isUserUnlocked()) return;
+     }
+
+     // Branch object initialization
+     Branch.getAutoInstance(this);
+   }
+
+   @Override
+   protected void attachBaseContext(Context base) {
+     super.attachBaseContext(base);
+     MultiDex.install(this);
+   }
+ }

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example">
  
		<uses-permission android:name="android.permission.INTERNET" />
  	<uses-permission android:name="com.google.android.gms.permission.AD_ID"/>

    <application
+       android:name=".CustomApplicationClass"
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">

        <!-- ... -->

        <activity
            android:configChanges="orientation|keyboardHidden|keyboard|screenSize|locale|smallestScreenSize|screenLayout|uiMode"
            android:name="com.example.MainActivity"
            android:label="@string/title_activity_main"
            android:theme="@style/AppTheme.NoActionBarLaunch"
            android:launchMode="singleTask">

+           <intent-filter>
+               <action android:name="android.intent.action.MAIN" />
+               <category android:name="android.intent.category.LAUNCHER" />
+           </intent-filter>

+           <!-- BEGIN BRANCH -->
+           <intent-filter android:autoVerify="true">
+               <action android:name="android.intent.action.VIEW" />
+               <category android:name="android.intent.category.DEFAULT" />
+               <category android:name="android.intent.category.BROWSABLE" />
+               <data
+                   android:scheme="http"
+                   android:host="@string/applink_host" />
+               <data
+                   android:scheme="https"
+                   android:host="@string/applink_host" />
+               <data
+                   android:scheme="http"
+                   android:host="@string/applink_host_alternate" />
+               <data
+                   android:scheme="https"
+                   android:host="@string/applink_host_alternate" />
+           </intent-filter>
+
            <intent-filter>
                <action android:name="android.intent.action.VIEW" />
                <category android:name="android.intent.category.DEFAULT" />
                <category android:name="android.intent.category.BROWSABLE" />
-               <data android:scheme="@string/custom_url_scheme"/>
+               <data android:scheme="@string/deeplink_scheme"/>
            </intent-filter>
+           <!-- END BRANCH -->

        </activity>

+       <!-- BEGIN BRANCH -->
+       <!-- Branch init -->
+       <meta-data android:name="io.branch.sdk.BranchKey" android:value="@string/branch_key" />
+       <meta-data android:name="io.branch.sdk.BranchKey.test" android:value="@string/branch_test_key" />
+       <meta-data android:name="io.branch.sdk.TestMode" android:value="@bool/branch_test_mode" />
+       <!-- END BRANCH -->
+
        <!-- ... -->

    </application>

    <!-- ... -->

</manifest>

npx cap update ios

import UIKit
import Capacitor
+import BranchSDK

@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate {

    var window: UIWindow?

    func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
        // Override point for customization after application launch
      
+       Branch.setUseTestBranchKey(true) // If you are using the TEST key
+       Branch.getInstance().enableLogging() // If you want to enable logging
+       Branch.getInstance().setRequestMetadataKey("insert_user_id", value: "value") // If you need to append partner metadata before initializing Branch 
+       Branch.getInstance().initSession(launchOptions: launchOptions)
        
        return true
    }

    func applicationWillResignActive(_ application: UIApplication) {
        // Sent when the application is about to move from active to inactive state. This can occur for certain types of temporary interruptions (such as an incoming phone call or SMS message) or when the user quits the application and it begins the transition to the background state.
        // Use this method to pause ongoing tasks, disable timers, and invalidate graphics rendering callbacks. Games should use this method to pause the game.
    }

    func applicationDidEnterBackground(_ application: UIApplication) {
        // Use this method to release shared resources, save user data, invalidate timers, and store enough application state information to restore your application to its current state in case it is terminated later.
        // If your application supports background execution, this method is called instead of applicationWillTerminate: when the user quits.
    }

    func applicationWillEnterForeground(_ application: UIApplication) {
        // Called as part of the transition from the background to the active state; here you can undo many of the changes made on entering the background.
    }

    func applicationDidBecomeActive(_ application: UIApplication) {
        // Restart any tasks that were paused (or not yet started) while the application was inactive. If the application was previously in the background, optionally refresh the user interface.
    }

    func applicationWillTerminate(_ application: UIApplication) {
        // Called when the application is about to terminate. Save data if appropriate. See also applicationDidEnterBackground:.
    }

    func application(_ app: UIApplication, open url: URL, options: [UIApplication.OpenURLOptionsKey: Any] = [:]) -> Bool {
        // Called when the app was launched with a url. Feel free to add additional processing here,
        // but if you want the App API to support tracking app url opens, make sure to keep this call
+       Branch.getInstance().application(app, open: url, options: options)
        return ApplicationDelegateProxy.shared.application(app, open: url, options: options)
    }

    func application(_ application: UIApplication, continue userActivity: NSUserActivity, restorationHandler: @escaping ([UIUserActivityRestoring]?) -> Void) -> Bool {
        // Called when the app was launched with an activity, including Universal Links.
        // Feel free to add additional processing here, but if you want the App API to support
        // tracking app url opens, make sure to keep this call
 +      Branch.getInstance().continue(userActivity)
        return ApplicationDelegateProxy.shared.application(application, continue: userActivity, restorationHandler: restorationHandler)
    }

        if statusBarRect.contains(touchPoint) {
            NotificationCenter.default.post(name: .capacitorStatusBarTapped, object: nil)
        }
    }
    
+   func application(_ application: UIApplication, didReceiveRemoteNotification userInfo: [AnyHashable : Any], fetchCompletionHandler completionHandler: @escaping (UIBackgroundFetchResult) -> Void) {
+        Branch.getInstance().handlePushNotification(userInfo)
+     }

}

+ import { BranchDeepLinks, BranchInitEvent } from 'capacitor-branch-deep-links';

  @Component({
    selector: 'app-root',
    templateUrl: 'app.component.html',
    styleUrls: ['app.component.scss']
  })
  export class AppComponent {
    constructor(
      private platform: Platform,
      private splashScreen: SplashScreen,
      private statusBar: StatusBar
    ) {
      this.initializeApp();
    }

    initializeApp() {
      this.platform.ready().then(() => {
        this.statusBar.styleDefault();
        this.splashScreen.hide();
+       BranchDeepLinks.addListener('init', (event: BranchInitEvent) => {
+         // Retrieve deeplink keys from 'referringParams' and evaluate the values to determine where to route the user
+         // Check '+clicked_branch_link' before deciding whether to use your Branch routing logic
+         console.log(event.referringParams);
+       });

+       BranchDeepLinks.addListener('initError', (error: any) => {
+         console.error(error);
+       });
      });
    }
  }

// optional fields
var analytics = {
  channel: 'facebook',
  feature: 'onboarding',
  campaign: 'content 123 launch',
  stage: 'new user',
  tags: ['one', 'two', 'three']
}

// optional fields
var properties = {
  $desktop_url: 'http://www.example.com/desktop',
  $android_url: 'http://www.example.com/android',
  $ios_url: 'http://www.example.com/ios',
  $ipad_url: 'http://www.example.com/ipad',
  $match_duration: 2000,
  custom_string: 'data',
  custom_integer: String(Date.now()), // Custom integers must be converted to a string
  custom_boolean: true
}

BranchDeepLinks.generateShortUrl({ analytics, properties }).then(function (res) {
  alert('Response: ' + JSON.stringify(res.url))
}).catch(function (err) {
  alert('Error: ' + JSON.stringify(err))
})

// optional fields
var analytics = {
  channel: 'facebook',
  feature: 'onboarding',
  campaign: 'content 123 launch',
  stage: 'new user',
  tags: ['one', 'two', 'three']
}

// optional fields
var properties = {
  $desktop_url: 'http://www.example.com/desktop',
  custom_string: 'data',
  custom_integer: String(Date.now()), // Custom integers must be converted to a string
  custom_boolean: true
}

var shareText = 'Check out this link'

// share sheet
BranchDeepLinks.showShareSheet({ analytics, properties, shareText })

// Optional fields
    var analytics = {
      channel: 'facebook',
      feature: 'onboarding',
      campaign: 'content 123 launch',
      stage: 'new user',
      tags: ['one', 'two', 'three']
    }

    // Optional fields
    var properties = {
      $desktop_url: 'http://www.example.com/desktop',
      $android_url: 'http://www.example.com/android',
      $ios_url: 'http://www.example.com/ios',
      $ipad_url: 'http://www.example.com/ipad',
      $match_duration: 2000,
      custom_string: 'data',
      custom_integer: String(Date.now()), // Custom integers must be converted to a string
      custom_boolean: true
    }

    var settings = {
      width: 2000,
      codeColor: "#3b2016",
      backgroundColor: "#c79200",
      centerLogo: "https://cdn.britannica.com/95/156695-131-FF89C9FA/oak-tree.jpg",
      margin: 3,
      imageFormat: "PNG"
    }

    BranchDeepLinks.getBranchQRCode({analytics, properties, settings}).then((res) => {
      this.picToView  = "data:image/png;base64," + res.qrCode;
    }).catch(function (err) {
      alert('Error getting QR code: ' + JSON.stringify(err) + err)
    })

var newIdentity = '123456'
BranchDeepLinks.setIdentity({ newIdentity: newIdentity }).then(function (res) {
  alert('Response: ' + JSON.stringify(res.referringParams))
}).catch(function (err) {
  alert('Error: ' + JSON.stringify(err))
})

BranchDeepLinks.logout().then(function (res) {
  alert('Response: ' + JSON.stringify(res.logged_out))
}).catch(function (err) {
  alert('Error: ' + JSON.stringify(err))
})

var eventName = 'my_event'
var metaData = { 
	customData: {
  	'custom_dictionary': '123',
  	'anything': 'everything' 
  }
}

BranchDeepLinks.sendBranchEvent({ eventName, metaData })

// get a list of all Branch standard events
BranchDeepLinks.getStandardEvents().then(function (res) {
  alert('Response: ' + JSON.stringify(res.branch_standard_events))
}).catch(function (err) {
  alert('Error: ' + JSON.stringify(err))
})

var eventName = 'ADD_TO_CART'
var metaData = {
  customerEventAlias: 'alias name for event',
  transactionID: '1234455',
  currency: 'USD',
  revenue: 1.5,
  shipping: 10.2,
  tax: 12.3,
  coupon: 'test_coupon',
  affiliation: 'test_affiliation',
  description: 'Test add to cart event',
  searchQuery: 'test keyword',
  customData: {
    "Custom_Event_Property_Key1": "Custom_Event_Property_val1",
    "Custom_Event_Property_Key2": "Custom_Event_Property_val2"
  }
}

BranchDeepLinks.sendBranchEvent({ eventName, metaData })

BranchDeepLinks.disableTracking().then(function (res) {
  alert('Response: ' + JSON.stringify(res.is_enabled))
}).catch(function (err) {
  alert('Error: ' + JSON.stringify(err))
})

var isEnabled = true
BranchDeepLinks.disableTracking({ isEnabled }).then(function (res) {
  alert('Response: ' + JSON.stringify(res.is_enabled))
}).catch(function (err) {
  alert('Error: ' + JSON.stringify(err))
})