Sony SGPT11 - Manual (Page 22)

About the GPS Function
The GPS (Global Positioning System) function provides location information by receiving signals from GPS satellites.
You can see the location where you are, where you are going, or directions to a destination on Google Maps with your tablet device
by using the GPS function.
Note
When other electronic devices are near your tablet device, electromagnetic waves or magnetic interference from those may
prevent your tablet device from providing accurate location information. Keep electronic devices away from your tablet device.
When your tablet device is in an area with poor reception of GPS signals, you may encounter positioning errors. To receive more
accurate information, avoid using your tablet device in the following locations.
Inside buildings or vehicles
In tunnels or underground
Under elevated tracks
Between tall buildings
In dense trees
In valleys
The GPS antenna is built in to your tablet device. If you cover the antenna with your hands or other objects while using the GPS
function, the positioning accuracy may deteriorate [Details] .