raw sensor access matters, so does calibration you can see some characteristics of devices here: https://developer.android.com/guide/topics/sensors/gnss https:

raw sensor access matters, so does calibration you can see some characteristics of devices here: https://developer.android.com/guide/topics/sensors/gnss https://developer.android.com/guide/topics/sensors/gnss Its relatively simple to jam GNSS signals since they are so weak. QZSS is a interesting formation since it is designed for urban environment (skyscrapers and canyons) The USA has no solution for shipping positioning outside of GPS...