Instabug - The top apps in the world rely on Instabug for beta testing, user engagement and crash reporting.
Sitecake - Drag and drop CMS for HTML websites. It's flat file CMS so it's pretty fast.
Bird Eats Bug - Saw a bug? Send an instant replay to engineers. It will come with console logs and everything. Developers will โค๏ธ you.
Anchor CMS - Free and lightweight blogging system
Sentry.io - From error tracking to performance monitoring, developers can see what actually matters, solve quicker, and learn continuously about their applications - from the frontend to the backend.
Textpattern - Textpattern is an elegant content management system that is free, open source software.