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.
Precursor - Precursor helps designers and developers communicate and collaborate in real time.
Swift Playgrounds - Learn serious code on your iPad in a seriously fun way
mi.team - Collaboration app with chat, task board & video conference
Angle 2 Mockups - A giant Sketch Library for creating app presentations
Justinmind - Define awesome experiences through wireframes & prototypes.