Concept wise, this game is set up for a good time-consuming experience with no clear objective (nothing negative :)). Try to polish the game more, especially the snake movement. Seems like the further your mouse from the snake, the faster it becomes, which is quite hard to create a good loop, since it will drastically slow down when players try to make one, and when reach for a new apple, it quickly goes out of hand. Perhaps a constant speed for the normal movement, and gaining more speed is the job of the upgrades, could make the game feel much more satisfying.
Just some thoughts on the game. Keep up the good work!
PS: SFX could help alot!