Great for conga drums

After trying several apps, this is the only one that truly stands out. It picks up the correct pitch of the drum, allowing you to find the notes you are looking for. I was able to get my LP congas with Remo Nuskyn heads tuned to C, A, G.
NOTE: Starting with ios 7, this app no longer works. Hopefully the developer can fix it soon.

Dj_groovy about PitchBot - Smart Chromatic Tuner, v2.3