UX Archive Animated - iOS apps animated user flows
Device Shots - Generate high-resolution device mockups using a screenshot.
Page Flows - User flow design inspiration for mobile & desktop
Facebook Design - Devices - Images and Sketch files of popular devices.
UX Recipe for iOS - Design checklist & estimation tool for your next UX project
Mockuuups Studio - Fast and easy way to create product mockups on macOS, Windows and Linux.