This device puzzles me a bit

[whs]

Newegg.com - BU-353-S4 Weather-proof USB GPS Receiver

This GPS receiver needs to be attached via USB.

Since power and data are transferred through the same USB cable from the BU-353, there’s no need for batteries or any other external power source.

But it also has Bluetooth capability (see specifications). For what does one need/use the Bluetooth if the GPS data is transferred via USB ?

 

[UsernameIssues]

Garmin (and other companies) make navigation systems that can be built into (or added to) a vehicle. These navigation systems can use bluetooth to access an external GPS antenna/receiver such as the one that you linked to. The USB power for the external GPS antenna/receiver can come from a power source other than a computer (like a dash mounted USB charging port or a converter). No traditional computer need be in the vehicle.

 

[whs]

OK, I understand that application. But if you run on a laptop or tablet, one could get away without the bluetooth connection - right? Although it may be an advantage to power the device via a USB charger and then connect with Bluetooth. Then the tablet is not tethered.

I was planning to use this device or whichever better device I can find on an Asus Transformer running this Microsoft program.

 

[UsernameIssues]

Correct, bluetooth need not be used... but like you mentioned, there might be times when it is nice to have the tablet/laptop free of wires. You could walk the tablet to another car in your caravan to discuss why the software thinks you should drive across a lake