Strava is an app used by many athletes to track their running and/or cycling, it monitors speed, distance, elevation, and averages it over multiple records. So how does this relate to Pyschogeography and Derive? Well within the app and online it has a GPS built in, assuming the recording device does, this allows users to track the route they take and see where they have been in the past. This is useful for Derives as it means users can track where they go and my group in-fact used it whilst in Amsterdam to track their own derives. Most likely an athlete will have pre determined the route but is useful if they did not and go on a Derive, knowingly or unknowingly.
The elevation aspect is also useful in relation to Pyschogeography as it monitors the geographical landscape and how in affected the journey of the user. See if they slowed down on hills or sped up on straights etc.
Some examples of my own Derives on a bike are:
As you can see in the last image it looks similar to a bird, this brings me onto Semiotics