Clockin is a simple iOS app that lists various timezones in a tableview. Each cell in the tableview includes an animated analog clock written in Swift using Core Graphics and UIKit.
This application is developed completly from scratch over a weekend. The purpose was to review developing apps using NSLayoutConstraints programmatically without a storyboard. And I must say, it's been quite fun to use it programmatically and I can see why it can be more efficient in some cases.
Full disclosure: The application has a few UI bugs mainly visible on iPad. Didn't have enough time to fix them.
Additionally, UIClockView & ClockTime is availble to use under the MIT License.