Pocket Solfeggio is an app for musical ear training.
It plays solfeggio sequences that help to improve musical perception and the recognition of chords, arpeggios, intervals and scales.
The musician can choose the sequence (triads, tetrads, scales, etc.), the key (tonality, by the circle of the fifths) and octave, the speed and also the instrument that will play the sequences.
The app also includes a progressive ear test where your goal is to recognize the chords that are played in various keys.