i still play Clash Of Clans and other games like that with no lag.
You cannot compare that. Clash of clans is a native game. C2 exports HTML5 games, that's like 50 more layers of abstraction Wrappers like XDK don't magically make a native game out of it, they just package a browser engine with it. It's still "just" a browser game.
The newer the tech, the less a problem this is. On modern phones you can make perfectly fine HTML5 games with Construct2 that that run at 60fps.
But not with an S2.