It's surprising how often I can get an okay-ish GPS signal indoors... it seems to have a lot more to do with building materials than anything else. Multipath r

It's surprising how often I can get an okay-ish GPS signal indoors... it seems to have a lot more to do with building materials than anything else. Multipath reflections means the location (and thus timing accuracy) wanders a lot, but it's still great down to microseconds if you can get 5+ satellites in view.