Built by a hardcore team, Crashlytics is an elegant solution to a big data problem. The most powerful, yet lightest weight crash reporting solution, they find the needle in the haystack, even the exact line of code that your app crashed on. Crashlytics is now part of Firebase.
Rollbar is a full-stack error monitoring platform for web and mobile applications. Rollbar help developers find and fix bugs fast. Built by developers for developers. Support for all languages, including - Javascript, Ruby, Python, PHP, Node, Golang, Flash, Android, iOS, more.
Airbrake is the leading exception reporting service, currently providing error tracking for 50,000 applications with support for 18 programming languages. Airbrake let developers build better software by giving detailed reports of errors in applications. Giving you insight into the health of your application in production. Airbrake give detailed exception reports that tell you what happened, what bit of code was responsible, and allow you to recreate the error for rapid debugging. Airbrake goal is to build the best developer toolset on the planet. One that gives you full stack insight, and allows you to build great software