Pulsar Music Player has long been one of the best music players on Android.
It is an offline audio player without advertisements. Its gorgeous user interface matches every single detail of the material design guidelines. Pulsar contains almost every necessary feature to fulfill all of your musical needs including: gapless playback, lyrics display, crossfade, play speed adjustment, tag editing, last.fm scrobbling, Chromecast, voice command, Android Auto, equalizer, music visualizer, audio balance, ReplayGain, sleep timer, etc.
System Requirements:
Requirements: Android 5.0+

The 821A is the first multitrack tape machine that doesn't use a transformer. It doesn't have a capstan or a pinch roller, so the tape path is free to move without any resistance or audio signal degradation.