3GP is an audio and video container format developed by the 3rd Generation Partnership Project (3GPP).
3GP is designed as a multimedia format for transmitting audio and video files between 3G cell phones and over the Internet. This format is commonly used by mobile phones that support video capture. This is part of the Mobile Broadband Standard. 3GGP uses AMR for a speech format.
The extension .3GP is also used on AAC sound files.