I am not sure what an iPad is capable of, but you essentialy need a device with GPS receiver that can record the traces. The web-based editor (Potlatch) uses Flash so it will not run on an iPad. JSOM is in Java - I am not sure if it works. Maybe there is some editor specially for iPad, but more likely you will have to use some computer.computer. Edit: See comments for recommended application.

I am not sure what an iPad is capable of, but you essentialy need a device with GPS receiver that can record the traces. The web-based editor (Potlatch) uses Flash so it will not run on an iPad. JSOM is in Java - I am not sure if it works. Maybe there is some editor specially for iPad, but more likely you will have to use some computer.