Adobe has release an update to their Photoshop Express software on iOS4 which now includes support for the iPad. Previously available for the iPhone the latest update will add a bit more real estate for users to make simply adjustments and crops to their photos on their iPad.
Having tried the earlier version on the iPhone I was a little disappointed - it did crash on a few occasions running version 3 of the iPhone software and the latest update doesn't really add any notable new features but has an updated user interface and better performance. From the feedback on the App store it probably needs a few more big fixes.
On the plus side this is very early in its development and I'm sure with such a big brand behind the software they will add more features and improve its stability. You also know that Adobe's experience will mean all manipulations should pretty accurate and colour adjustments standardised along side their desktop software - at least as much as possible on mobile devices. And to be fair it is free.
You can currently do basic things such as crop, rotate and adjust colour of your photos and also use the artistic filters such as soft Focus, sketch, color-manipulation tools - including Exposure, Saturation, Tint, Black and White, and Contrast. The effects include Vibrant, Pop, Border, Vignette Blur, Rainbow, Warm Vintage, White Glow, and Soft Black and White.
Another big feature is the ability to manage and upload photos to your photoshop.com account if you have one and its obvious this is something Adobe are really trying to push.
You can check out a video demo for the iPhone version here.