A free app for Android, by Diego Forever.

Lithium Video Player is the best app for watching movies and TV shows on your Android phone or tablet. It’s a free and simple app with a clean and intuitive interface, and the latest version is available for Android 4.4+ and above. It supports most video files, including MP4, MOV, MKV, AVI, WEBM, etc. It can also play music files and even audio clips and podcasts.

It supports multiple audio formats and can play music in the background. It also supports subtitles and has an advanced audio player.