This is one of those games that works really great on mobile platforms. It's kinda like Flappy Bird but also not. This isn't a genre I make or play or lot of myself so it is a bit hard for me to give proper advice or feedback, and I don't want to repeat what everyone else has already pointed out in the comments. Maybe consider making the cannons move or change positions so it won't be so easy to hover between cannons, but otherwise I don't have a lot unique feedback, a lot of the other comments already pointed out a lot of great stuff to consider