The synthesizer VA-beast is real good and have a lot of possibilites that includes an advanced sample player that is integrated into the synthessizer engine (plus sequencer tracks) which can be purchased seperately or as part of G-Stomper Studio.
The G-Stomper Rhythm is the Groovebox part triggering samples if feeling that the synhesizer part is not important...
Anyway three highly recommendable apps in either case...
Google Play G-Stomper Studio:
play.google.com/store/apps/details?id=com.planeth.gstomper
Google Play VA-Beast:
play.google.com/store/apps/details?id=com.planeth.vabeast
Google Play G-Stomper Rhythm:
play.google.com/store/apps/details?id=com.planeth.rhythmkey