Convert audio and video directly on the device using FFmpeg ffmpeg.org/

FFmpeg is a set of open source libraries that allow you to record, convert digital audio and video recordings in various formats. It includes libavcodec, a library for encoding and decoding audio and video, and libavformat, a library for multiplexing and demultiplexing into a media container. The name comes from the name of the MPEG and FF expert group, meaning fast forward.
FFmpeg is already built into the program and does not require downloading additional codecs.
The conversion takes place directly on the device (the Internet is not required), and the conversion speed depends on the processor speed of the device.

Supports: MPEG4, h265, h264, mp3, 3gp, aac, ogg (vorbis and theora), opus, vp8, vp9 and many other formats (you will find the list in the app).

Requirements: Android 4.4 and the availability of the processor ARMv7, ARMv8, x86, x86_64.

FFmpeg with x264, x265, ogg, vorbis, theora, opus, vp8, vp9, mp3lame, libxvid, libfdk_aac, libvo_amrwbenc, libopencore-amr, speex, libsox, libwavpack, libwebp, librtmp

More options can be found in the help pages for FFmpeg.

For Android 11 users: New rules require the application to use more confidential methods of working with files on your device. You will have to copy/move the input files to a shared folder, such as DCIM, Movie, Music, Download. Sorry for the inconvenience

From version FFmpeg Media Encoder 4.4.1_3:

Updated x265 lib
For Android 11 and above, the working directory has been changed

Variant
Arch
Version
DPI
(x86) (Android 4.3+)
Latest: 4.0.5 on October 7, 2020
(x86) (Android 4.4+)
Latest: 4.4.1_2 on December 31, 2021
All versions
FFmpeg Media Encoder 4.4.1_3

Version:4.4.1_3

Uploaded:January 24, 2022 at 10:51AM UTC

File size:26.45 MB

Downloads:307

FFmpeg Media Encoder 4.4.1_2

Version:4.4.1_2

Uploaded:December 31, 2021 at 3:27PM UTC

File size:26.45 MB

Downloads:158

FFmpeg Media Encoder 4.4.1

Version:4.4.1

Uploaded:December 23, 2021 at 2:26AM UTC

File size:26.42 MB

Downloads:74

FFmpeg Media Encoder 4.4_7

Version:4.4_7

Uploaded:December 22, 2021 at 10:25PM UTC

File size:26.42 MB

Downloads:60

FFmpeg Media Encoder 4.4_6
December 22, 2021

Version:4.4_6

Uploaded:December 22, 2021 at 8:17PM UTC

File size:26.45 MB

Downloads:20

FFmpeg Media Encoder 4.4_5

Version:4.4_5

Uploaded:April 28, 2021 at 1:35PM UTC

File size:24.52 MB

Downloads:282

FFmpeg Media Encoder 4.4_3

Version:4.4_3

Uploaded:April 27, 2021 at 9:21AM UTC

File size:24.52 MB

Downloads:57

FFmpeg Media Encoder 4.4_2

Version:4.4_2

Uploaded:April 27, 2021 at 5:01AM UTC

File size:24.52 MB

Downloads:42

FFmpeg Media Encoder 4.4

Version:4.4

Uploaded:April 26, 2021 at 3:07PM UTC

File size:24.52 MB

Downloads:46

FFmpeg Media Encoder 4.0.5

Version:4.0.5

Uploaded:October 7, 2020 at 10:42AM UTC

File size:23.97 MB

Downloads:598