Really Good UX - A library of screenshots for UX inspiration
Instabug - The top apps in the world rely on Instabug for beta testing, user engagement and crash reporting.
UX Archive Animated - iOS apps animated user flows
UserTest.io - User testing made simple. High-quality, affordable user testing solutions from real users, here in the UK. Improve your usability!
FlowMapp - FlowMapp is a UX planning tool for creating visual sitemaps and user flow.
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!