Yes i use mine got a BT gps unit jemco for £9 off fleabay then look for BTroq on cydia and hay ho you have sat nav plenty off info on google how to do it, also use the unit on my 10inch vega using copilot use tomtom on the touch.
You can use IGO on the iphone so may work on an ipod, it can be found in all the best places for free. Personally I think IGO is way better than tomtom on any device.