Hi! In the Windows Phone store there is Sky Media Player. It is free, but to play formats that you have written are paid. In this app can buy the codecs for video formats. Supported formats - .flv, .mkv, .vob, .qt, .m2v, .ts, .mts, .f4v, .hdmov, .moov, .mpeg, .mpg, .mpe, .mpeg4, .divx, .dvx, .ogv, .mxf. Maybe this info will be useful for you