We’ve been doing a lot of work recently with GPS for the upcoming iRide tracker system. In particular, working with the GLONASS service which allows us to accurately pinpoint location using just a handset’s in-built positioning sensors.
Pretty much all smartphone’s these days have a combination of GPS and GLONASS sensors. This allows the phone to calculate location, speed and elevation without the need for a wifi / 4G connection. Instead it uses a process called Trilateration. Not a lot of people know that.
We took this data and compiled it with overlay software and existing mapping data to give speed, elevation, gradient, distance and direction readings. So far, it seems to be working well.