I have five tuners as apps and this one tunes me sharp compared to the others. That is a problem especially on the low E on my acoustic guitar. The other annoying feature is the needle that jumps all over the place. I dont recommwnd this app. There are more accurate apps and after all that should be all you want from a tuner.
Jurij m about PitchBot - Smart Chromatic Tuner, v1.2.1