The app "FiLMiC Pro 2" was just announced today and I have tested it. Turns out you can record at 60fps and the quality of the video is amazing. All of you who have used previous version of this app know that this option was there before but it wasn't working well. It has improved greatly and I can recommend you guys to download it because recording at 60fps is a lot better than 30fps or lower. And also now you can zoom in and out while recording video!
http://itunes.apple.com/us/app/filmic-pro-2/id555853307?mt=8
http://itunes.apple.com/us/app/filmic-pro-2/id555853307?mt=8