You can share GPS on one WiFi enabled Android phone with another WiFi enabled Android phone by a free Android App, TetherGPS Lite.
TetherGPS (TGPS) can be launched by using the launch buttons in its configuration. Another way of launching it is by using included 1×1 widgets through intent broadcasting from other apps.
How to use Tether GPS Lite
We are showing here you an example of using it. Say you have 2 phones: one HTC Evo and other Nook Color.
Now, connect both the phones on the same network, or tether Nook Color to Evo with an android wifi tether. Run TetherGPS Server on Evo and TetherGPS Client on Nook Color. The Nook will receive GPS data from your Evo phone. You can use your apps on Nook such as Google Navigation and Google Maps using shared GPS data.
Points To Note:
1. On Client device, Mock Locations are enabled. To enable this, go to Settings –> Applications –> Development –> Allow mock locations.
2. On both devices, GPS location must be enabled.
3. You should use TGPS Client and Server widgets to enable services.
4. TGPS Lite includes the client and lite version of the server which will run for 5 minutes at a time and after that the time-limit; server can be restarted via widget.
5. If you are unable to see widgets in widget list, check to see if the app is installed on your phone and not on SD Card.
6. If there is no way to enable GPS navigation on your phone, you can download any free GPS toggle widgets from the Android Market.
7. TetherGPS uses the following intent listeners for activation by Tasker and other apps:
Video showing Tether GPS Lite in Action