Are the GPS coordinates a good source of entropy? Are the GPS coordinates (latitude and longitude) a good source of entropy? If yes, why? If no, why?
The question would investigate on the fact if the GPS location data can be used as source of entropy in the cryptography field, in general. The question could be trivial or not, it depends by several factors (e.g. the scenario, the entity speed and so on).
But what do you think about it?
Probiably not.  If a hacker where to locate the device physicaly then the search space would be greatly decreased.  Even knowing the city (ip can give you that) might be enough.
Other similar sources with a higher entropy could be changes in lat and long, but those are most likely small.
You would most likely get better entropy using the accelerometer/gyrometer/magnomiter instead (if avaliable, I am assuming this is for a phone).
If you wanted lots of entropy, you could ask the user to give their phone a nice toss while poling gyro and acceleration.