Ruskul Thanks to you for your benchmarks
Despite benchmarks, I found that on my android device with snapdragon 800 cpu Asm.js often causes some micro freezes of 0.1 seconds circa, instead box2dweb runs smoothly.
The situation is opposite on pc where asm.js perfectly simulates and box2dweb causes those micro freezes.
I'll give a try to chipmunk, but I need to say I could never develop my android/iOS game without box2dweb.