Can't determine color management used by iOS in the new ipad. Which is best to export from lightroom 4 to ipad 3? sRGB, Prophoto..???
iPads are effectively devices with (a) no color management at all, but (b) screens that are natively fairly close to sRGB.
So you should export in sRGB.
There is a viewer app that incorporates color management, but the color management only works for the specific app, not generally across the device: http://spyder.datacolor.com/portfolio-view/spyder-gallery/