https://soundcloud.com/darlitglitch/disturbed
At it's base, it's a simple loop, but I find it enjoyable.

https://soundcloud.com/darlitglitch/hard-hitting
A good use of two soundpacks I no longer have.

https://soundcloud.com/darlitglitch/unmade
A creative use of the few soundpacks I still had at the time.

What I personally think of as my three best sounds that have been made with a free music app on my phone.