Instabug - The top apps in the world rely on Instabug for beta testing, user engagement and crash reporting.
Refined GitHub - Browser extension that makes GitHub cleaner & more powerful
UserTesting.com - Usability testing has never been easier. Get videos of real people speaking their thoughts as they use websites, mobile apps, prototypes and more!
GitZip - Download or create a download link for a GitHub project folder/sub-folder or file.
UserTest.io - User testing made simple. High-quality, affordable user testing solutions from real users, here in the UK. Improve your usability!
GitHub Hovercard - GitHub Hovercard provides neat hovercards for GitHub.