OMG... how many people are having problems with this... i must write tutorial for this.
Use this: ... utions.png
Set this as the last layer and when all is done just delete it and compile your game.
Set project window and layout sizes to 640:960 and basicly set everything important (that needs to be seen) into the smalest screen aspect ratio (iphone4) and make sure that background covers both biger aspects (iphone 5 and ipad) and your good to go... and spawn everything that needs to enter screen from outside those bigger aspect ratios!
(if you are more expirienced than you can use anchors to stretch visible objects to fit into every aspect ratio)
use scale outer and set in your Layout "unbounded scrolling" to YES.
Hey man, i have tried window and layout sizes 640:960 and i have this result on my EMULATOR.
I send in attachments.