How I Use It
I would not use this app for music instruction. Individuals might enjoy "picking out" the melody of popular songs, but the app is not a good teaching tool. Though you can adjust the keyboard size, it is not a realistic experience that would translate to an actual piano keyboard. The app "teaches" a melody by showing you which keys to press. It doesn't address key signatures, choral structure, time signature, etc. Even under the guidance of a music teacher, this app would not be a useful supplemental tool.
I am a classically-trained pianist, former K-8 music teacher, and piano instructor. This app claims to teach users how to play by ear. However, there is no guided instruction built into the app. Users just "play" along with lighted keys. The app only indicates the melody of a song and I question the accuracy of the interpreted melody in several of the tunes I tried. For example, for Adele's "Someone Like You", the app "teaches" the piano ostinato, not the song's melody. The classical "melodies" are almost unrecognizable. Piano Melody Free is not an educational app and I'm surprised Graphite even reviewed it in the first place. Not only would I not recommend it to other teachers, I would caution my music students to avoid this app.