Hello. This is probably a pretty rare circumstance, so I thought I would ask the pros.
I recently purchased an Android Headunit for my car (Eonon GA7150A). It runs Android Marshmallow. In order to have a data connection, there is a USB port in the back that receives 3G (see Accessory #8 on the Eonon site).
This means I need a USB dongle with a SIM slot to connect into it. I'm in the USA and use Project Fi. I have already received my data-only SIM from Google. From my research, it appears you need a device that can access T-Mobile's LTE network and most likely need to manually set the APN. I asked Fi Support directly and they had no answer for me.
Does anyone have experience with USB SIM dongles and/or can recommend one? I'm not sure how one sets the APN, so I dont know if it could be done through the android menus on the headunit or if it needs to be done on the dongle itself (perhaps through a PC connection)