I have played this for about five solid hours now, and I love a lot about it. The art is great, the controls are easy, the story is funny, the medals fit and are not hard to figure out (although close call took me a bit), and most of all: upgrades are all very useful and not too difficult to come by, which means I can keep playing and still get somewhere!
That being said, a couple of things in this game have been troublesome:
1. When you get going fast enough, bats don't appear until they are in the middle of your screen, making timing difficult.
2. The music does not line up well (for me) with the character of the game, and induces headaches after ten minutes looping. Props for having music, and a mute button, but something lighter in the future might be less aggravating.
3. The mini games are easy, but almost too easy. They also aren't worth that much, which means if you beat them first try (I did), there isn't much point in going back unless you want to farm gems.
4. The water background has nothing but the mines and bats to assist you. More often than not, that's where you'll be stuck for several hours worth of gameplay, despite breezing through the first two areas.
5. One super minor thought I've had is that when this little critter turns into a meteor, the heat radiating outward from him should kill all enemies, if not also smash those gems for me- it would be a good incentive to attempt to get to the top of the screen frequently.
I do agree with the idea that this could be a fun game on a phone, with a little tweaking of controls. Trust me, I do love this game, but those problems may mean I will not come back to this game tomorrow.