Basically remember the sequence and repeat. Not bad at all, very basic and a little slow but well polished. I would like to see a little more to it in order to hold my attention. Perhaps you can customise different instrument sounds for the keys or the concept could be auditioning for a band and you can choose your instrument. For example if you choose to be the drummer you get just purcussion. then you have to complete sequences to pass auditions etc.... I don't know, just thinking out load :)
well done.