Optimization... Since I started developing games I know the true meaning of this word.

Since I'm developing on xamarin I now what optimisation means

It's surprising how weak computers are when you're trying to render what seems like not that much stuff. Then all of a sudden you need to do complicated magic to make it all work "ideally™"

What kind of optimization? :D

IMHO frustum Culling is standard and not "optimisation"

Wasn't refering to culling. Trying to render as many things as possible with as few draw calls as possible is tricky business... Especially if you also want your stuff to be interactive. You'll optimize rendering in one way which will slow things down in another way.