Have someone tried to export the simple physics catapult example to CocoonJs? I tried and the results disappoint me... tested on iPhone 4 and iPad 2, it begins with 55 fps (cool) but When i Touch the pig, all slow down to 4/5 fps.
I test another physics game i made, a Ragdoll with 12 parts put together, the big part was 12x10 pixel, Very small. The result was that When the Ragdoll begin to fall, with only floor on the screen and a restart button, the results was the same as above, 4/5 fps.
So, if u are planning to make an Angry Birds clone, u can't put it on any smartphone or tablet but only on pc (on the pc the fps was 60 fps, perfect).
I'm a big fan of C2 and I love it, but I Think this is a Very limitation for Who, like me, Wanna create a physics game not only for the Chrome store...
Haven't try the AppMobi, if someone would like to try and tell the results...