You don't need the add-on to tether to an Android application called "DSLR Controller". Look it up and see if the 1Dx is a compatible body. I use it with the 5D bodies. Uses a USB connection so your tablet needs a USB fitting, which the ASUS "Transformer" units put in their keyboard attachment. Asus also makes an adapter for USB to attach to the tablet all by itself, if for any reason you don't want to use the keyboard.
I have no experience using the app to begin geo-tagging each image, though. And the images aren't stored on the tablet... your card continues to be the storage location. But they might have incorporated changes since I last looked, as many people wanted the dev to allow off-camera storage.