
specs
3GP is defined in the ETSI 3GPP technical specifications. 3GP is a required file format for video and associated word / audio media types and timed text in ETSI and 3GPP technical specifications for IP multimedia subsystem (IMS), multimedia messaging service (MMS), multicast / multimedia streaming service ( MBMS)) and transparent end-to-end Streaming Service (PSS) packet switching.

3G2 is defined in the 3GPP2 technical specification.
Technical details
The relationships between the ISO Base Media Format file format, the MP4 file format, the 3GPP file format, and the 3GPP2 file format. Based on the 3GPP2 technical specification published on May 18, 2007.
The 3GP and 3G2 file formats are structurally based on the ISO core multimedia file format defined in ISO / IEC 14496-12 – MPEG-4 Part 12, but earlier versions of the 3GP file format did not use some of its features. . 3GP and 3G2 are container formats similar to MPEG-4 Part 14 (MP4), which is also based on MPEG-4 Part 12. The 3GP and 3G2 file formats were designed to reduce storage and bandwidth requirements to accommodate cellphones . They are good for low-end smartphones for fast, free streaming.

3GP and 3G2 are similar standards, but with some differences:
The 3GPP file format is designed for GSM-based phones and can have the file extension of .3gp
The 3GPP2 file format is designed for CDMA-based phones and can have the file extension .3g2
Some mobile phones use the .mp4 extension for 3GP video.
3GP
The 3GP file format stores video streams like MPEG-4 Part 2, H.263 or MPEG-4 Part 10 (AVC / H.264) and audio streams like AMR-NB, AMR-WB, AMR-WB +, AAC-LC, HE-AACaacPlus v1 or advanced (v2 HE-AAC). 3GPP allowed the use of AMR and H.263 codecs in the ISO base file support format (MPEG-4 Part 12), because 3GPP specified the use of voice templates and fields in the ISO base media file format, as well as the definition of new boxes to which codecs refer. These extensions were registered by the registration authorities for code points in the ISO basic multimedia file format (“MP4 family” files). For MPEG-4 media specific information storage in 3GP file, 3GP specification refers to MP4 and AVC file format, which is also based on ISO base multimedia file format. The MP4 and AVC file format specifications describe the use of MPEG-4 content in the ISO base multimedia file format.
A 3GP file is always big-endian, it stores and transfers the most significant bytes first.
3G2
The 3G2 file format can store the same video streams and most of the audio streams used in the 3GP file format. Additionally, 3G2 stores audio streams as EVRC, EVRC-B, EVRC-WB, 13K (QCELP), SMV or VMR-WB, which was specified by 3GPP2 for use in ISO base multimedia file format. The 3G2 specification also defined some enhancements to the 3GPP timed text. The 3G2 file format does not store advanced audio streams aacPlus (HE-AAC v2) and AMR-WB +. For storing MPEG-4 media (AAC audio, MPEG-4 Part 2 video, MPEG-4 Part 10 – H.264 / AVC) in 3G2 files, the 3G2 specification refers to the MP4 file format and the specific format of AVC file, which describes the use of these contents in the ISO base multimedia file format. For storing H.263 and AMR content, the 3G2 specification refers to the 3GP file format specification.
device holder
Most 3G-capable mobile phones support 3GP video recording and playback (memory, maximum file size for playback and recording, and resolution limits exist and vary).
Some newer / higher-end phones without 3G capabilities can also play and record in this format (again, with such limitations).
Imported audio from CDs to a PlayStation 3 when configured to encode MPEG-4 AAC copies on USB devices in 3GP format.
The Nintendo DSi and Nintendo 3DS family support .3gp on an SD card.
Apple iDevices used to support files for playback only as pass-through files, so there are no editing options, but since iOS 9 files mean this format has been deprecated, they have to be manually converted to H.264.



