VJay, from the makers of DJay for iPhone, is mixing software for videos much like a DJ setup, but instead you'll record, mix, and add audio and effects to create cool-looking video mashups.
The interface is sleek-looking and fairly easy to use with a little bit of digging around. It is set up with video screens on the bottom on both sides, then the main viewing window up top. On each side you can touch a button to add a video source and work with playback and loop controls. You also have a button that brings up tools for syncing the beats per minute (BPM); an Equalizer to adjust levels; a section for reverse, slow-mo, and slice controls; and a place to fine-tune effects. While a video is playing, you can even "scratch" video by touching and swiping back and forth in the smaller video screens on the bottom.
VJay comes with several generic action clips (all copyrighted) in the Featured section that you can play with, but you also can use videos from your camera roll and even videos downloaded from iTunes. Obviously, if you were using this app in a set professionally, you'd have to watch out for copyrighted material there as well.
With that said, VJay could definitely be used professionally (with your own clips) in a number of settings where video-mixing could take any celebration to the next level or just for making video mashups. The app offers several pro-level effects to add to clips. On each side of the main window on top, you get a display for each video that's currently queued up. Below that you can choose from four effects including Strobe, Twirl, Fisheye, and Crush, that all affect both the audio and video in the clip. Even better, VJay offers transition options on the fader slider that make switching between your two videos seamless and professional-looking.
Though the many tools are not obvious initially, after spending some time with the app, I was able to dig around and get a pretty good video mix going with no experience whatsoever. The app also has links to accessories you can buy, such as a digital AV Adapter, a Griffin DJ Cable, or Numark iDJ Live, if you want to use the app in a professional or party setting.
Overall, VJay is a powerful video-mixing app with tons of controls to work with to make pro-level mashups a lot like the way a DJ spins and mixes records. If you're a DJ and want to add video-mixing to your gig repertoire or if your just a hobbiest who wants to put together video mashups, VJay is a great app for the job.