I just recently discovered cooconjs and i was excited to learn in a week or two. However i also have discovered crosswalk from intel.
Both look very promising And i have no idea which one is better for making games run faster on cellphone.
In article here: https://www.scirra.com/blog/133/introducing-crosswalk-the-new-way-to-publish-to-android it says that it is really fast and asmjs code can actually can get close to native mobile apps. If chrome now can run amsjs compatiable code faster than it should be true..doesn't cooconjs run the chrome version too but without all dom.