TrackJS JavaScript Error Logging - JavaScript Error Monitoring from TrackJS gives you context about what's happening in your end-users' browsers.
Bugfender - Cloud logging for your apps, not only crashes matter
Rollbar - Rollbar collects errors that happen in your application, notifies you, and analyzes them so you can debug and fix them. Ruby, Python, PHP, Node.js, JavaScript, and Flash libraries available.
Bird Eats Bug - Saw a bug? Send an instant replay to engineers. It will come with console logs and everything. Developers will ❤️ you.
CatchJS - Unbloated, yet feature rich. CatchJS provides JavaScript Error Tracking the way it should be.
Marker.io - Visual feedback and bug reporting tool for websites