Okay...I am very pleased with this Android app - for it's tuning accuracy. And I just ordered the adapter for electronic devices to make it even more useable in noisier environments. It is VERY accurate. My only disappointment is the lackluster support for Android devices as compared to Apple products. This IS a Five-Star recommendation based on the quality of the tuning possible, however Android users take note that there are significant feature disparities (perhaps making this a Three or Four-Star product for you, at best.) I am not sure why there is such a bias by Peterson for Apple. Even the name of the app conveys this. However, surely - in the real world of musicians - there are as many Android users as there are Apple users. I sincerely hope that Peterson will take this review in the spirit it is intended, and make a great product much better by paying additional attention to potential customers who may not have drunk the Apple Kool-Aid.