P.S. - I did my tests with use wireless to determine location (AGPS) on and off and it didn't really seem to make much difference.
FYI "Use wireless to determine location" is not aGPS. It is land based tower location, not satellites.
aGPS is part of GPS, which uses only satellites, and only information from the data networks to better see the satellites.
The aGPS/GPS on the Epic has several bugs, some trivial (misreported accuracy) one quite serious: symptoms of failure to clear assistance data. Assistance data, which helps you lock satellites quickly, can if a few hours old and therefore incorrect, create problems as your device will see the satellites but not lock them. *
EssentiallySmartphoens go through steps depending on what signals they can receive, specifically satellites and/or towers, and use the most accurate available.
It seems the software on the Epic is not stepping through the process as logically as other smartphones. Almost all other smartphones today will resolve a location and send it to applications(AGPS with satellties in about 30 seconds or less if ourtside, or Tower estimate in about 30 seonds or less if inside.)
If you find yourself going for over a minute outside with aGPS (which is ticked on with enable GPS on the Epic, not the use wireless networks) or over a minute inside with "use wireless networks" ticked on, you may be well advised to
cycle the phone with an on off cycle, as several of us believe from testing that the Epic is essentially sticking with bad prior data which will be cleared with a reset.
*Ephmerics assitance data needs to be less than four hours old or the device will see satellites buthave trouble locking on and placing them in use. Almanac assitance data expires over the longer term, and stale alamace will exihibit more as a falure to see some satellites. at all. Most smartphones will see and use 11 satellites whiel standing under a clear sky with few to no obstructions giving you very high location precision.
