news to me ....once a route is in the phone there would be no need for "incoming data"...and it would download in the background anyways.
Still unconvinced spending hundreds on a dedicated GPS when you have it in your phone anyways is good use of funds.
The camera focus thing is real and likely not a good idea to put an expensive phone on the bars...mine voice navigates fine from my pocket.
Lots of used phones - this would be fine and no need to buy a plan to use a phone as gps.
If you want visual nav with a phone ...the bright screen and gps eats battery so either needs a usb socket or a power pack.
Earlier phones were not waterproof but there were cases.
Phones give you music, books, picture taking and internet from wifi sites plus you GPS nav all for $100 or so.