iOS Design Kit - The newest library of native iOS templates
Xcode - Xcode is Apple’s powerful integrated development environment for creating great apps for Mac, iPhone, and iPad. Xcode 4 includes the Xcode IDE, instruments, iOS Simulator, and the latest Mac OS X and iOS SDKs.
Dashboard UI Kit - A modern & responsive dashboard UI kit for designers.
Angle 2 Mockups - A giant Sketch Library for creating app presentations
Bots UI Kit - Fully customizable Sketch UI Kit for Messenger Platform
Balsamiq Mockups 3 - New public beta for the popular prototyping tool