3GA is a 3GPP audio file created in 1998. It was created by the 3rd Generation Partnership Project. It is used mainly on mobile devices in order to record, play and transmit audio data. 3GPP (3rd Generation Partnership Project) is a consortium that develops specifications for mobile telephony. The format resembles 3GP files, however, it includes only audio data. In most cases, 3GA files are used by mobile phones in order to record and transmit audio data. For example, this is how audio is recorded in Samsung Galaxy phones. The .3GA file extension can be changed to .3GP, which is widespread. Everything is supported by many programs. The 3GA format uses an adaptive coding audio codec with variable speed (AMR, AMR-NB, GSM-AMR). The development of this codec was done in order to compress encoded speech signals using adaptive modulation. In 1999, the 3GPP consortium adopted the Adaptive Variable Rate Coding (AMR) standard. Currently, it is used by GSM and UMTS communication systems. It is this format for speech recording that has found wide application on mobile devices. We note at the same time that it is not possible to play such files very often on certain devices.
MPGA is one variation of the common digital audio file format (or MPEG Audio). The full name of this format is MPEG-1 Layer 3 Audio File. MPGA format is considered standard for Windows and is supported by all players of this operating system. Any multimedia software that supports MP3 format can work with MPGA audio files. MPGA files are small in size and have significant compression, and file compression is performed without loss of quality and preserving the original sound. The massive use of MPGA is related to the Android mobile OS.