i dont know
maybe i don' t use c2 as well ... but believe me my game is simple ... and i see difference between iphone 4 and 4s using ejecta
i have trying all issues ... enable collisions only when it is necessaire , families, event group, avoiding every tick, using spritefont for score, and all performance tips on tutorial for c2 (optimize image size as it is used on game,avoid transparent,avoid clear background to no etc....).... i get some result .... but still same
on xcode
cpu usage is 80%
memory usage is 86 mb
fsp is between 37 and 42