Sentry, founded in 2008 and headquartered in San Francisco, is the leading open-source error tracking and performance monitoring platform serving 100,000+ teams. It supports 40+ language SDKs, APM distributed tracing, and Session Replay, with both SaaS and self-hosted deployment.
Raygun, founded in 2013 and headquartered in Wellington, New Zealand, is an application performance platform combining crash reporting, APM, and real user monitoring in a unified solution with SDKs for iOS, Android, and Web.
Bugsnag, founded in 2011 and headquartered in San Francisco, CA (acquired by SmartBear in 2020), is an error monitoring platform specialized in mobile and web application stability with SDKs for iOS, Android, React Native, Flutter, and more.
Countly is an open-source product analytics platform founded in 2012 in London, offering self-hosted and cloud deployment with native mobile and web analytics, crash reporting, push, and A/B testing, with 15,000+ deployments worldwide per official materials.