UsbNmea 앱
UsbNmea is an Android application that aims to offer some support to USB GNSS antennas on Android.
Currently, it only saves the messages that it gets from the antenna to a file on your phone. I have made another app to convert that file to a GPX (as long as the output from the antenna follows the NMEA standard), but I recommend using GpsBabel on your laptop instead.
UsbNmea starts a service that should stay on in the background, which gets the data from the USB antenna and saves it into a file. To get the data from the USB antenna, I use the UsbSerial library from Felipe Herranz. Since his code is licensed under the MIT license, I decided to do the same for my code. If you like that, you can support him through the options he lists in the README of the UsbSerial library.
