I'm aware of those tips Ashley.
Weird that I can't find the debug icon or option. My construct license is the early adopter.
I am aiming to mobile webapp, so this is important. I have around 100 objects (sprites, sprite-font,etc). This was enough to slowdown my iphone 4 safari's performance.
I imagine that the process that handles the graphical drawing can't calculate whether or not some object is or isn't visible if laying behind other objects (Z-Order). In that case everything must be drawn.
I did a bit tedious job to add besides moving top/bottom of layers, to enable/disable visibility.
And once again I can press a button on iPhone and feel no delays, much more responsive! So, whenever you can, you should set invisible what you don't want to see. Don't know if the out of screen position trick works. The next optimization here should be to also disable all collisions of those invisible objects.