Wow, for a first time this is really well put together! Great job!
The visuals might be a bit simple, but the gameplay is very solid. It controls a bit harsh maybe, but it's very addictive. Ended up with 11011 points and didn't wanted to stop playing.
Like the others said, the first time I picked up the wings it took my by surprise and was a very welcome surprise. And it was nice to get better upgrades along the way.
Also had fun "cheating" a bit with the jumping, when I discovered that after you press F or A/D, you could do a double-jump. Not sure if that was intentionally, but I felt clever to discovering that and using that sometimes to make higher jumps possible.