this would show perfectly useful for people living in the EU where the 25km/h maximum speed limit is enforced. so you would be able to lock the speed limit to 25 km/h where needed (for exemple on the roads) and unlock it everywhere else. This could be done either by keying in a code,pressing a certain sequence of keys,or through the app.
for exemple like this one
BBSHD 68, 73, 100, 110, 120mm - 48v 1000w/1500w - Kit moteur pédalier 8FUN