Maximum size of UIImage tiles for iPhone 4

I have an iPhone app containing a large static image, which is sliced into 1024x1024 tiles and put in an UIScrollView. I'm not clear whether I can use larger tiles on the iPhone 4.

If I want to support a double-res image for iPhone 4, should I:

1. Create 2048x2048 tiles with a @2x suffix or
2. Create 4 tim开发者_运维技巧es as many 1024x1024 tiles and write logic to load in these tiles on the iPhone 4

For iPhone 4 create 2048x2048 tiles with a @2x suffix. Then you have not change your code. Just add these images.