It's funny... I found the rate of fire to be way too slow, the movement speed to be way too fast, and the collision on the pickups way too precise... but I overall was having a lot of fun! Maybe because of how those things all came together?
The pathfinding for the apples was really well done so they'd always bunch together coming from 90 degree angles. It made me feel like I could strategize and not just react and it led me to discovering the satisfying explosion from taking out several of them in one shot
One idea to consider might be giving different attack patterns to the different color apples rather than just speed. Like maybe green apples come at you from diagonals