Originally Posted by
Adlerdriver
Perhaps it's liability thing. Can't throw it all back at the pilots when they have a runway incursion at 300 RVR if they can claim the iPad made them do it.
The iPad or Surface doesn't have the inertial references calculations or PRAIM to know when it isn't in the correct position. My iPad and iPhone occasionally tell me they're somewhere else when they're not. But the airplane alerts you as soon as it detects a problem and suspects the position is incorrect. Plus those devices only have one GPS receiver.