Crashlytics is a powerful and lightweight tool that delivers interactive, detailed crash reports in realtime. Crashlytics performs deep analyses of each thread and uses a multi-symbolication process to provide progressively higher levels of detail. It is one of the modular kits contained within Fabric and is available in both iOSand Android versions.
Bugsnag monitors application stability, so you can make data-driven decisions on whether you should be building new features, or fixing bugs. Bugsnag helps in improving the user experience of your applications by giving up much needed information that guarantees to positively drive your builds.
Instabug helps maximize the test environment and success of your application by offering In-App Feedback and Bug Reporting for your mobile applications. Instabug assists you by gathering comprehensive feedback from your beta testers and also having live conversations with your users.