Hello, I'm considering buying navigon since it offers live traffic info in my country while tomtom doesn't. I will change iphone in a motnh or so with the new iphone 4. Since traffice live is an in-app purchase, how does this work when changing phones? Is it a one-time purhcase for EACH device? does it get synced back to itunes then reinstalled in any other phone I use? So I guess the question is wether I buy traffic live now or wait until I get the new iphone! thanks.