I am a professional opera singer, I decided to try this because I get bored in my hotel and I wanted to see how well it worked from an already trained musicians perspective. It is a fun little game I guess but it doesnt actually register the right pitches most of the time, even with the slightest vibrato the app freaks out and assumes youre wrong, since mine is very even I would say either its not well tuned enough to input what is happening, or it is too delicate that even a semi tone waver makes it decide your pitch is wrong. Maybe works with the pop singing school of thought but the fundamentals of singing and matching pitch are better learned from a local voice teacher or sitting with a piano. Wish it went through scales and solfege or even note names instead of non sense syllables and this could have some value other than a gimmick.