This is a nice simple game, and I could see it expanding into something quite addictive.
One thing that bothered me was that sometimes it took a little bit of time (less than a second, but still noticeable) between my finger press and the game responding to it. And the collision detection is a little off, so the spike hitboxes are a little larger than the sprite itself.
Thanks for the feedback!
As soon as we get our current project released, I will update this game.
I'll fix the things you mentioned. We were also thinking of creating a global highscore list, which should be fun.