What you need:
- Intuitive (most important -- convenient rewind)
- Support for MKV and MP4 containers
- Support of subtitles in srt format
- Variable speed playback
The latter condition can be sacrificed.
A nice rewind -- MX Player for Android: swipe horizontal shakes for a period, depending on the length of the swipe, at the same time, until you release your finger, see how many moves (video
). Example uncomfortable rewind: VLC with a tablet interface (also a swipe, but the length of the jump is unpredictable).