Is it possible to use a stylus on a capacitive touchscreen? (perhaps by ensuring it has the same capacitance as a finger - a small finger).
I found editing maddening on an iPad because of the inaccuracy. You can roll your finger to adjust the cursor position, and the magnifying window helps, but it's not as good as simple cursor keys (disclaimer I was just trying it out in an apple store, so there may be ways around this problem that I don't know of).