Our iOS App is completely built in Swift. Still early adaptor, but a great language!
Most of our newer apps are written completely in swift, with our older ones and some special cases using a mix of Swift and Objective-C, but with Swift 2, the language is pretty much a must-use. "guard" is <3.
Newer apps are being written with Swift instead of Objective-C.
Getting ready to move parts of the app to Swift. Love the Playground.
Native iOS application development.
Native iOS APP and Middleware with Swift Perfect.
Swift on a way to fullstack - it is moving to the backend