I've exported this journey as a TCX course and also as an activity (links go to the exported files). I then imported both into LocusMap on Android. The average speed is shown to be 14.5 km/h.
Why's that?
In my profile => preferences, I've set the average speed to 20.1 km/h.
My expectation would've been, that the speed is taken from the preferences.
Comments
I have to admit I didn't realise anyone actually used the TCX average speed for anything - it was hardcoded simply because the file format requires timestamps! But I've just made it so that it'll pick up your speed preference as suggested - let me know if that works for you.