From Peak Systems:
Diptic Video is the perfect photo app for quickly creating and sharing video collages. Diptic Video's core features include:
Combine up to four video clips or still photos (or a combination of both) in one of 35 layouts. You can use photos/video clips saved to your device or take a video/photo on the spot with your device camera.
Option to trim (shorten) your video.
For video clips less than 16 seconds, you can change the playback mode. Standard playback is Forward and other options include Forward + Reverse, Reverse, and Reverse + Forward.
You have the option to play video clips in slow motion or double time! You can also loop your video clips so they play on repeat.
Play your video clips at the same time or one after another via Sequential Playback.
Add music from your iTunes library to video clips.
Swap videos/photos between frames.
Round the inner borders, as well as modify thickness and color.
Pan, rotate, mirror and zoom individual photos and videos.
What's new in this version:
You can now reverse videos that are longer than 15 seconds (through trimming).
Option to play your videos clips in slow motion and double time.
Bug fixes and other enhancements.