Top Free Mobile Monitoring Tools and How to Integrate Them in Android & iOS Apps

If you're building mobile apps, performance and error monitoring are no longer optional — they're essential. In this article, I’ll walk you through the top free tools I’ve used to monitor mobile applications, and I’ll show you how to integrate one of them step-by-step in both Android and iOS.

Why Mobile Monitoring Matters

When I launched my first app, I had no idea users were experiencing crashes. The Play Store showed only generic crash reports. It wasn’t until I integrated a monitoring SDK that I saw the full picture — including stack traces, slow screens, and even user interactions leading up to the issue.

Top Free Mobile Monitoring Tools (2025)

Here are some of the best free tools I’ve tested for mobile monitoring:

• Firebase Crashlytics (by Google) – Real-time crash reporting for iOS and Android
• AppSignal – Free for small apps, includes performance monitoring
• Sentry – Tracks errors, crashes, performance bottlenecks; supports React Native, native apps
• Bugsnag – Free for solo devs, rich UI for crash diagnostics
• Instabug – More focused on bug reporting and user feedback

For this article, we’ll focus on Sentry, because it offers a generous free tier and supports both native and hybrid stacks.

How to Integrate Sentry in Android (Java/Kotlin)

Step 1: Add the SDK to your project

// In your root build.gradle
buildscript {
  dependencies {
    classpath 'io.sentry:sentry-android-gradle-plugin:4.3.0'
  }
}

// In your app build.gradle
plugins {
  id("io.sentry.android.gradle")
}

dependencies {
  implementation 'io.sentry:sentry-android:6.35.0'
}

Step 2: Initialize Sentry in your Application class

import io.sentry.android.core.SentryAndroid;

public class MyApp extends Application {
  @Override
  public void onCreate() {
    super.onCreate();
    SentryAndroid.init(this, options -> {
      options.setDsn("https://YOUR_PUBLIC_KEY@o123456.ingest.sentry.io/1234567");
    });
  }
}

Now, any uncaught crash or exception will be reported automatically.

Optional: Manually report an error

try {
  // Some risky operation
} catch (Exception e) {
  Sentry.captureException(e);
}

How to Integrate Sentry in iOS (Swift)

Step 1: Install via Swift Package Manager

https://github.com/getsentry/sentry-cocoa.git

Step 2: Initialize in AppDelegate.swift

import Sentry

func application(_ application: UIApplication,
  didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
  
  SentrySDK.start { options in
    options.dsn = "https://YOUR_PUBLIC_KEY@o123456.ingest.sentry.io/1234567"
    options.debug = true // Debug mode for development
  }

  return true
}

Optional: Manually capture error

SentrySDK.capture(error: myError)

What You Can Monitor with Sentry

• Crashes with full stack traces
• Breadcrumbs (user actions before a crash)
• App performance (cold start time, slow screens)
• Device + OS info

The dashboard is very intuitive. I was able to detect and fix 3 critical crashes within the first week of using it — crashes that never showed up in Google Play's crash reports.

Alternatives Comparison

Tool	Best For	Free Tier	Platforms
Firebase Crashlytics	Basic crash reporting	Unlimited	Android, iOS
Sentry	Detailed error & performance monitoring	5K events/mo	Android, iOS, RN, Flutter
Bugsnag	Professional UI, session tracking	Free for 1 user	Android, iOS

Conclusion

If you're building a mobile app, monitoring isn’t a luxury — it’s a necessity. With tools like Sentry or Crashlytics, you can detect bugs before your users complain, and improve your app’s quality with real data.

You don’t need to pay, and you don’t need a backend team. Just pick the right tool, follow the steps above, and you’ll be surprised how much insight you’ll gain from day one.