Earlier this year I mentioned a nice collection of interesting animated transitions and a tutorial on using the transition API that was added with iOS 7.
Here’s another nice open source library that simplifies use of the transition API and providing a number of custom transitions and interaction controllers from Raizlabs called RZTransitions.
RZTransitions provides a wide number of animation, and interaction controllers, and provides a simple api for using custom transitions and you can mix and match all the included transitions and interaction controllers for interesting effects.
Here’s an animation from the readme showing off some of the included transitions:
You can find RZTransitions on Github here.
A great library for creating different transition effects.