This could be, if someone in the market takes it on, a great way to gain quick inexpensive market share. $20-$30 for a decent TBT navigation app including one country/state map, then an in app purchase (that Apple is saying will be possible) of each additional map needed (something like $10 each country/state).
Some start up is going to try it.....
I really see, as the mobile phone market matures with reliable TBT navigation (others already have it), that all the standalone TBT unit sales dwindle to nothing in the next 3-5 years, as well as a dwindling market for it to be 'in car'.
Just ask the wrist watch manufacturers. How many teenagers/20/30 somethings out there do you still see wearing a wrist watch (not to go off topic, just something parallel to think about)?