Firebase provides a comprehensive suite of tools for Android development. This guide covers essential Firebase services: Analytics, Cloud Messaging (FCM), and Dynamic Links.

Table of Contents

  1. Setup
  2. Firebase Analytics
  3. Firebase Cloud Messaging (FCM)
  4. Firebase Dynamic Links

Setup

Add Firebase to Your Project

  1. Add the Firebase project in the Firebase Console
  2. Download google-services.json and place it in your app module
  3. Add dependencies:
// Project-level build.gradle
buildscript {
    dependencies {
        classpath 'com.google.gms:google-services:4.3.15'
    }
}

// App-level build.gradle
plugins {
    id 'com.google.gms.google-services'
}

dependencies {
    implementation platform('com.google.firebase:firebase-bom:32.0.0')
    implementation 'com.google.firebase:firebase-analytics-ktx'
    implementation 'com.google.firebase:firebase-messaging-ktx'
    implementation 'com.google.firebase:firebase-dynamic-links-ktx'
}

Firebase Analytics

Firebase Analytics provides insights into app usage and user engagement.

Basic Event Logging

val firebaseAnalytics = Firebase.analytics

// Log a simple event
firebaseAnalytics.logEvent(FirebaseAnalytics.Event.SELECT_CONTENT) {
    param(FirebaseAnalytics.Param.ITEM_ID, "id123")
    param(FirebaseAnalytics.Param.ITEM_NAME, "Product Name")
    param(FirebaseAnalytics.Param.CONTENT_TYPE, "product")
}

Custom Events

fun logViewItem(tag: String, category: String, packageName: String) {
    val bundle = Bundle().apply {
        putString("Tag", tag)
        putString("Category", category)
        putString("PackageName", packageName)
    }

    firebaseAnalytics.logEvent(FirebaseAnalytics.Event.VIEW_ITEM, bundle)
}

Predefined Events

Firebase provides predefined events for common scenarios:

  • FirebaseAnalytics.Event.ADD_TO_CART
  • FirebaseAnalytics.Event.PURCHASE
  • FirebaseAnalytics.Event.SIGN_UP
  • FirebaseAnalytics.Event.LOGIN
  • FirebaseAnalytics.Event.VIEW_ITEM

Debugging Analytics

Enable Verbose Logging

adb shell setprop log.tag.FA VERBOSE
adb shell setprop log.tag.FA-SVC VERBOSE
adb logcat -v time -s FA FA-SVC

Debug View (Real-time)

Send events directly to the Debug View in Firebase Console:

# Enable debug mode
adb shell setprop debug.firebase.analytics.app your.package.name

# Disable debug mode
adb shell setprop debug.firebase.analytics.app .none.

Best Practices for Analytics

  1. Use Categories: To distinguish data within events, use category parameters
  2. Consistent Naming: Follow a consistent naming convention for custom events
  3. Don’t Over-log: Focus on meaningful events that provide actionable insights

Firebase Cloud Messaging (FCM)

FCM enables push notifications and messaging to your Android app.

Setup

class MyFirebaseMessagingService : FirebaseMessagingService() {

    override fun onNewToken(token: String) {
        // Send token to your server
        sendTokenToServer(token)
    }

    override fun onMessageReceived(remoteMessage: RemoteMessage) {
        // Handle notification
        remoteMessage.notification?.let { notification ->
            showNotification(notification.title, notification.body)
        }

        // Handle data payload
        if (remoteMessage.data.isNotEmpty()) {
            handleDataPayload(remoteMessage.data)
        }
    }

    private fun showNotification(title: String?, body: String?) {
        val intent = Intent(this, MainActivity::class.java).apply {
            addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP)
        }

        val pendingIntent = PendingIntent.getActivity(
            this, 0, intent,
            PendingIntent.FLAG_ONE_SHOT or PendingIntent.FLAG_IMMUTABLE
        )

        val channelId = "default_channel"
        val notification = NotificationCompat.Builder(this, channelId)
            .setSmallIcon(R.drawable.ic_notification)
            .setContentTitle(title)
            .setContentText(body)
            .setAutoCancel(true)
            .setContentIntent(pendingIntent)
            .build()

        val notificationManager = getSystemService(NotificationManager::class.java)
        notificationManager.notify(0, notification)
    }
}

Manifest Configuration

<service
    android:name=".MyFirebaseMessagingService"
    android:exported="false">
    <intent-filter>
        <action android:name="com.google.firebase.MESSAGING_EVENT"/>
    </intent-filter>
</service>

Get FCM Token

FirebaseMessaging.getInstance().token.addOnCompleteListener { task ->
    if (task.isSuccessful) {
        val token = task.result
        Log.d("FCM", "Token: $token")
    }
}

Topic Subscription

// Subscribe to topic
FirebaseMessaging.getInstance().subscribeToTopic("news")
    .addOnCompleteListener { task ->
        if (task.isSuccessful) {
            Log.d("FCM", "Subscribed to news topic")
        }
    }

// Unsubscribe from topic
FirebaseMessaging.getInstance().unsubscribeFromTopic("news")

Push Delivery Challenges

Push notification delivery rates can vary significantly, especially in regions with network issues:

Factors Affecting Delivery

  1. Network connectivity
  2. Battery optimization settings
  3. Device manufacturer restrictions (e.g., Xiaomi, Huawei)
  4. App background restrictions

Dynamic Links are smart URLs that direct users to specific content based on context (app installed, platform, etc.).

Features

  • Short Links: Google-provided shortened URLs
  • Smart Routing: Different behavior based on app installation status
    • App installed: Open specific screen (deep link)
    • App not installed: Redirect to Play Store or custom URL
    • Desktop: Redirect to web URL

Firebase Console

  1. Go to Firebase Console > Dynamic Links
  2. Create a new dynamic link with:
    • Long link URL
    • iOS behavior
    • Android behavior
    • Campaign tracking options

Programmatically

val dynamicLink = Firebase.dynamicLinks.dynamicLink {
    link = Uri.parse("https://example.com/product?id=123")
    domainUriPrefix = "https://example.page.link"

    androidParameters("com.example.android") {
        minimumVersion = 125
    }

    socialMetaTagParameters {
        title = "Check out this product"
        description = "Amazing product description"
        imageUrl = Uri.parse("https://example.com/image.png")
    }
}

val dynamicLinkUri = dynamicLink.uri

val shortLinkTask = Firebase.dynamicLinks.shortLinkAsync {
    longLink = Uri.parse(dynamicLink.uri.toString())
}.addOnSuccessListener { (shortLink, flowchartLink) ->
    // Short link created
    Log.d("DynamicLinks", "Short link: $shortLink")
}

class MainActivity : AppCompatActivity() {

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        handleDynamicLink()
    }

    private fun handleDynamicLink() {
        Firebase.dynamicLinks
            .getDynamicLink(intent)
            .addOnSuccessListener { pendingDynamicLinkData ->
                val deepLink: Uri? = pendingDynamicLinkData?.link

                deepLink?.let { link ->
                    // Handle the deep link
                    val productId = link.getQueryParameter("id")
                    navigateToProduct(productId)
                }
            }
            .addOnFailureListener { e ->
                Log.e("DynamicLinks", "Error getting dynamic link", e)
            }
    }
}
Scenario Behavior
App installed Open app to specific screen
App not installed (mobile) Redirect to Play Store
Desktop Redirect to configured web URL
Instant App enabled Launch Instant App

Campaign Tracking

Add UTM parameters for campaign tracking:

val dynamicLink = Firebase.dynamicLinks.dynamicLink {
    link = Uri.parse("https://example.com/promo")
    domainUriPrefix = "https://example.page.link"

    googleAnalyticsParameters {
        source = "email"
        medium = "newsletter"
        campaign = "summer_sale"
    }
}

Best Practices

Analytics

  1. Use meaningful event names and parameters
  2. Enable debug mode during development
  3. Test events appear in Debug View before release

FCM

  1. Handle both notification and data payloads
  2. Create notification channels for Android 8.0+
  3. Test on various device manufacturers (especially Chinese OEMs)
  1. Always provide fallback URLs
  2. Use social meta tags for link previews
  3. Track campaign performance with UTM parameters

Troubleshooting

Analytics Events Not Appearing

  1. Check if debug mode is enabled
  2. Verify internet connectivity
  3. Wait up to 24 hours for events to appear in dashboard

FCM Token Issues

  1. Ensure Google Play Services is available
  2. Check if app is properly configured in Firebase Console
  3. Verify google-services.json is up to date
  1. Verify domain prefix is properly configured
  2. Check if app SHA fingerprints are registered
  3. Test with Firebase Dynamic Links Test Tool

References