Aside from the walljump/screenshake/lag issue that people are mentioning, this game is the perfect melding of platformer and canabalt style running game. The walljumping does also take away from the sense of speed, so maybe a sequel could dump it, or have it reverse your momentum and launch you right off, instead of gripping first.
FYI: if you die, via the baselisk for example, after getting the cannon, and you already have the ball, you can't use the cannon. Since i don't want to play through again to find out, how much damage does the cannon do?
Great game/tool. Two suggestions: First, give the gallery a search artist/work option. Then you can find out what else your favorite artists have done or find a work without scrolling back forever. Second, someone mentioned a better color management system and I agree wholeheartedly. give a colorwheel type option, or at the very least, give a brown color and a skin-tonish color. Other than that, this is an addictive digital art program.