As I recall, GetImage's coordinates are based on the actual device resolution so trying to get an image greater than that will not work as intended. It is pretty confusing and not very desirable for many use cases. The help states:
Quote: "Note that the image produced by this command is not guaranteed to have the same width and height as those given to the command, this is because the image is created from a portion of the screen which has a different size on different devices. For example, with a virtual resolution of 480x360, you would get an image of the full screen by calling this command with a width of 480 and a height of 360, but on an iPod this would produce an image of 480x360 pixels, whilst on an iPad it would be around 1024x768 pixels."
Render Images are also currently restricted to powers of 2 on mobile or bad things happen. Paul mentioned this may be amended as part of the 3D command work but who knows when that may be. Due to these problems I can't create particular applications I had in mind using AppGameKit and must use an alternate platform.
You could likely create the final image at the intended resolution using memblocks but that obviously gets more complicated.
