Starstruck

It takes a truly sick and twisted mind to create a nearly impossible screen with spike traps, and then to actually place a glowing "double jump" powerup lower in the screen, mocking you as you die 100 times...

*dies by spikes* *dies by spikes* *dies by spikes* AARRGG GIMME DOUBLE JUMP!!! XD

This game has potential, despite being lots of game like that. Only thing you should actually take care of is making the game actually challenging, with normal difficulty curve, and not 'high spike of difficulty, down with it [passage betweeb spikes] then again high spike [second spikes - celling], down again, and minor spikes of difficulty, with gradual degradation of it, and rare spikes of it [like 'hit the really small square in the air'] ;)
I just hope my feedback will be of use. [sorry for double post, hit limit of signs per comment]

I'm afraid this isn't what one calls 'good game'. Reasons are : challenging games are not necesarily incredibly frustrating to lack of control; only thing you actually DID to make it 'challenging' is fast game speed, and thus - reduction of controls of game itself. About the game - upgrades are in at least... strange order... as Samboskull said : at time you get acid immunity you have most likely encountered only 2 [litelary] acid packs that were making this AP upgrade slighly problematic to get... other thing is : why do you get BOTH AP and Spike Immunity at nearly same time ? single jump well timed makes this game way too easy... Did I mention double jump being later accessible, only to get to few places ? Let's be honest - double jump should rather be means to avoid spikes, not to be completely immune to them by time you get it...

Challenge should arise from interesting gameplay, not from a jump function that's about two pixels more than needed to clear an obstacle, making it so that if you don't hit it at exactly the precise time you fail.