So you read up on how there’s at least some cellular coverage with your newly acquired navigation phone/tablet, but you just called AT&T, and they said it’s not compatible, now what?
Well, there’s still good news, as you generally have two options
Option 1: Find an alternative carrier
For some, this might not be the favorable option, as they like to keep all their accounts/devices under one umbrella, I get it. But for others, especially depending on what your use-case is, how much data you actually need, or how you plan on using the device, it might simply be a better option.
There are many different MVNO (Mobile Virtual Network Operators), these are basically the smaller carriers that lease unused bandwidth from the top carriers like T-Mobile, AT&T, or Verizon. They usually come with the same coverage as the big boys, but at much lower prices. In some cases, they’re even cross-network, meaning they’ll operate on T-Mobile or AT&T networks at the same time, giving you even more options for coverage.
One player in this space that I’ve used personally in the past is Ting. Ting offers flexible plans on both T-Mobile and Verizon’s networks. And the best news, you can register the DMD-T665 or DMD-T865 directly with them, no jumping through donor phone hoops (see below). I haven’t done extensive testing with every MVNO, but most seem to work, but not all will recognize the IMEI which is often required for registration, or flat out tell you it’s not compatible; which is why you’re probably here to begin with. In those cases.
Update: So the Ting success might be a YMMV (Your milage may vary) - as I've had reports from other users that their IMEI was not accepted for a direct registration.
Option 2: Donor Device
This essentially requires using a donor device. Older Android devices are all over the place these days, and can be had for as little as $25 on the used market. All you need is a device that runs the same network frequencies you plan on using (3G / 4G), and preferably be unlocked from any carriers.
Once you have a device, simply register it on either your existing plan, or with a new carrier if you opt to go with a cheaper MVNO (see above), and get your SIM card. Once you have the SIM card either by mail, or from a store, simply place it into your Nav Phone/Tablet and BAM you’ve got service on your device.
Again, you may not have perfect service, coverage may be limited compared to a phone known to be fully supported on that network, but from my testing, the devices I’ve used (DMD-T865, DMD-T665, and Carpe-Iter Tab v4b) all work in some way on most carriers/networks.