Curves are a pretty versatile and powerful feature of any image processing application when you know how to use them, especially if you want to try and automate parts of your workflow.
The replacement Eye-Fi software I’m working on utilises curves for its presets, so the technique shown above is a good way to create curves adjustment files that give good approximations of various looks.
Then I can have them apply automatically as I shoot as each image pops up on the iPad screen..