Most often, players for music and for audiobooks are different, but there are solutions 2in1. One of them is in front of you. As an eReader, the app allows you to bookmark (in unlimited quantities), it has a sleep timer, control playback speed and playback. There's even this unusual feature, as a change of pace for a few octaves. A normal player all this would not be necessary.
as for more standard functions, we need music lovers, there is a built-in equalizer, Visualizer interesting, a scrobbling in Last.FM complements all is a set of widgets and various themes.

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