If it's anything like the extremely terrible devices in their current vehicles, those are custom device similar to existing off-the-shelf GPSes. If they're in any way based on Android, they've gone well out of their way to completely replace the UI with something entirely unlike Android.
The new devices are actually much different than the clunky old ones you're referring too. I wouldn't be surprised if they were exactly a commodity Android tablet.
It looks like they've changed the hardware, but the Hertz Neverlosts that I used in 2005 and 2006 were vastly superior to a 2015 smartphone.