Yesterday I installed a USB Port to charge the phone or supply power to the GPS. Very easy installation.
The dual port I bought is this one, paid $13.

I removed the inline fuse since the switched ACC1 connections are fused. It comes with a really long cable so you can connect it directly to the battery or if you want to go from the front of the bike to the space under the seat. I only needed around 30cm (2') of wire since I installed the port on the left black radiator cover with double stick tape.
This is the bracket where the port sits. You can remove the port when you need to take the radiator covers off.


Port installed



Wiring connections and routing


The red/yellow wire is positive, brown is negative.
You can see the dielectric grease oozing out of the transparent OEM connectors. The blue are the shrink blade terminal connectors that I used and shrunk them with my heat gun.
That's all. Easy. Useful. Simple. Cheap.