In china, find my iPhone is off by 500m northwest. This makes it hard to find your phone location. Because this location is off Find my Friends is also off by the same amount. How can you meet your friends if your location is showing right but their location is 500m off when you are standing right next to them. In that app your own location is sampled by the Maps program which is right but your friends location is from their own Find my IPhone. Meaning the location is wrong in iCloud updating. Maybe the gps coordinates is right but shows wrong.
