I'm operating from a Samsung Galaxy Tab 7.7, which natively supports 32-bit color depth. Is photoshop touch rendering at this level? or is it 16-24 bit color. not sure i could tell without comparing two images from actual screens.
basically from what i gather, the answer is at that photoshop touch, in its ability to render psd, jpg and png is at least using a color space providing 24 or 30 bit color depth. the device's color space is capable of rendering 32 bit color depth.