This game is very original. the idea of playing music along birds in the forest is great, and the graphics are really pretty and set the mood perfectly.
A couple of things made the game very hard for me. mainly, the birds sing too often so it was hard to figure out what notes i was playing, as many times it would overlap with the birds. maybe longer periods of silence between each instance of the bird singing could make it easier for the player to practice and be able to try different progressions.
Also I found the learning curve too steep for me, i think the second combination was way more complex and fast-paced than the first.
It's a great concept, that probably could benefit from being easier in the beginning and progressing to more challenging progressions.