From Ghost Mobile:
The Video Converter can convert nearly any video files to MP4, MP3, 3G2, AAC, AVI, FLAC, FLV, M4A, MKV, MMF, MPEG-2, OGG, WAV, WEBM, WMA or WMV. 1. Choose your input file from another app (like your email or dropbox). You can also transfer from a PC. 2. Choose your output file format (like MP4, MP3, MKV, etc). 3. Convert. It will only take a few seconds. 4. Watch your video, add to library, send to DropBox or email, etc.The Video Converter can convert FROM just about any format (including MOV, AVI, MP4, MKV, WMV, etc) TO the following formats: MP4, MP3, 3G2, AAC, AVI, FLAC, FLV, M4A, MKV, MMF, MPEG-2, OGG, WAV, WEBM, WMA or WMV. You can convert your video to another video format, or extract just the audio and output an audio format. After conversion is complete, you can watch the video or easily open it in another app, like dropbox or a video player, and you can always get all your converted files on your computer with iTunes File Sharing. Note: Files must be under 400MB, which is enough for most mobile videos. Access all your converted files through the in-app file browser. Conversions usually take less than 1 minute. Conversion is done on a secure server, which makes conversion easier and more battery-friendly. You must have an internet connection to use this app. Files are immediately deleted from the server upon conversion. Note: Your files will be sent to a secure conversion server for conversion. While the files are immediately deleted after conversion or cancellation, you should be aware that by using this app, you agree that your files are sent over to internet to the conversion server.