Is anot a very popular media container format designed for mobile phones; works with standard CDMA2000. The main difference from other media containers, 3GP, is the lack of support for AAC format audio tracks.
Is a the most popular media container format on phones without the support of 3G, which is currently somewhat outdated. Its main advantage is a compactness. Video data here gets stored in h.263 or MPEG-4 formats. AAAC-LC or AMR-NB are available for audio.