iOS doesn't support color profiles.
Maybe you should read more before you type.
Just because they don't provide you a way to assign a color profile does not mean iOS does not support color profiles... They have to because different devices now support a number of different gamuts.
iOS relies on a fixed resolution.
No, no it does not. It does specify things in points, but at this point there are a lot of iOS devices that are not just double the resolution of the original iPhone...
iOS supports all kinds of technologies that render at whatever resolution you have. From various Core Graphics drawing primitives to advanced image scaling stuff that makes full use of the GPU. I can take a PDF and drop it into Xcode to use as an asset anywhere in the app.
It also of course uses autolayout quite heavily in development, which will happily adapt UI elements to any kind of resolution differences it may encounter.