iPad painting apps

[jmw]

There are a handful of painting apps out there that people seem to generally really like; Brushes, Art Studio, Sketchbook Pro...

Do any on them allow you to export of file with layers that you can then open in Photoshop? Also, do any of them support larger resolution canvases than the iPad's native resolution? I'm looking at getting an iPad at the moment, I'd appreciate any info.

[tumbra]

Sketchbook Pro allows you to email images to yourself as PSD file while maintaining the layers. I like SBP, but there can be improvements. You know artist always bitchin.