first of all, its pretty strange you have better performance without webgl,
i would say its your graphic driver thats need updating, but then again if it happens on ios, that couldn't be the case
maybe its a genuine bug with the canvas render and tilemap, as most people are using webgl, it could be undetected
best would be to try to reproduce it in a smaller project and post a bug
Ok, I find a ""solution""....
depends of the windows size and the scale setting...
I was use 1280 x 720 on windows size( the resolution of iphone 5s)... I try different test, now I use 960 x 640 without scale, and is working.
but I think this problem is very important to solve, because if depends of the resolution screen and the windows size, maybe when I will try on ipad or different apple device the problem appear again and again... this make a serious problem if you like to make your game in iOS.
another serius point (this is about cocoonJS and not construct2 maybe) is:
when you active the webGL and test your project on iphone (with wi-fi), the battery will be very hot (never seen before like this), and in you have the iphone on charge, the battery still go down!! if you use like 10 sprite is the same, it's the webGL to take a lot or resources maybe.
so, webGL for cocoonJS is a big problem, but if you don't use the webGL, the performance is incredible, you can make a very big map with a lot of sprite and the performance is unbelievable off course, maybe if you use the tilemap (I consider the tilemap very important)
now, if with the next resale of construct2 and of cocoonJS solve this problem is perfect, and I think is good idea to fix it (if the problem is about the rendering,windows size etc... maybe it's easy to fix it)
Ribis I hope you will succedd.
thank you very much, I hope too eheheh