GPS Tracking Indoors

[learning]

I want to track and get info on some physical objects placed inside a building and get their Geographic location i.e Lattitude/Longitude
I know iPhone provides coordinates but I am not sure how accurate their are, especially since its inside the building.

I'm guessing any GPS device will struggle giving info due to no open space.
How good is GLONASS enabled devices vs GPS for this purpose? Any better and any specific devices that can give fairly accurate details for this purpose

[gary67]

Standard GPS is still only to within a few M's as the US military still won't let us go to mm accuracy like they have.

[psycik]

I thought the only way of doing location identification inside is by use to beacons - which are bluetooth based and multiples of them to triangulate the location.

[Jen]

What about RFID? You would need to place reference points in the building in order to identify locations.

[Eliza23]

When the GPS tracking device loses sight of the sky due to the blocking effect of the building structure, it will continue to report its location periodically as it was just before it entered the building.

Not only would the tracking device be reporting stale, out-of-date location data, there may be a long acquisition delay (possibly several minutes) upon exit as the GPS receiver regains a positional fix.

I have heard infsoft work for that.