TestFlight - iOS beta testing on the fly.
LibHunt - LibHunt tracks mentions of software libraries on relevant social networks. Based on that data, you can find the most popular projects and their alternatives.
Boombox.io - iOS devs rejoice! Embeddable HTML and hosted TestFlight beta sign-up forms.
AlternativeTo - AlternativeTo lets you find apps and software for Windows, Mac, Linux, iPhone, iPad, Android, Android Tablets, Web Apps, Online, Windows Tablets and more by recommending alternatives to apps you already know.
Applivery - Mobile Apps distribution system for Continuous deployment, Beta testing, Feedback, Bug reporting & Enterprise App distribution.
GitNews Web - Trending repositories from GitHub, HackerNews & Reddit