Hey nice job!
I really like the vibe of this one, has some nice original mario bros vibes :)
I feel like the grid option detracts from your game though. To me it looks better with it off and when its on it doesn't look as much like the gameboy to me. If this had a bit more consistency in the platforming physics I could have fun with it for a long time! I found the mid-air control a bit frustrating - but perhaps that is part of the charm! :)
Keep up the great work!