God job, I'm sure I have one of these upstairs, except this one has better pre-built songs, drums and recordings are a nice feature as well. 

It was fun, it reminded me of when I was a kid. It's simple but nicely executed. I just wish there was a function to stop playing the melodies, maybe I missed it? 

Nice feature set and samples in a pleasant package. The two-octave keyboard layout is great. The samples might need some trimming or fading at the ends because they tend to click for me. There are some minor quirks, like how starting playback will not cancel recording, or the re-rhythm feature doesn’t work so great with polyphony. Nice work!