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I learned coding on a C64 - The sucky resolution is nothing I want ever to have again.

What you currently want has little to do with what is usable... especially to any other developer with very high mobility needs/desires, or just on an extremely tight budget.

When I'm at my desk, I want dual 27" monitors.

However I prefer NOT to be stuck at my desk, especially when the weather is nice. Thus I currently do most of my iOS app coding on my MBA 11. Works great.
 
I think the most important part is not the size of the screen, but the resolution it is capable of.

I'm working on an 13" macbook retina running on 1680 x 1050 and have good enough overview on everything.

For 1024 x 768 your screen is too small to even show the whole iphone simulator on the screen, you will get a scroll screen from top to bottom of the simulator :p
 
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