Recently I had an issue on my new iPhone 4S after updated to iOS 5.0.1, which is very annoying: When I restart my iPhone 4S, no matter how, the location service just COMPLETLY WON'T work in ANY APP including Map App (under Wifi). So many users also reported this problem:
https://discussions.apple.com/thread/3482844?start=0&tstart=0
But, I finally figured out how to fix with more than 15 times turn-on and off by testing my phone, here is how:
It seems the problem (BUG) is come from the "wifi (or 3G) CONNECTION DELAIED TO GET location info after restarting your iPhone 4S" and it's always happends on password protected phones. Which means when you use the password protection and then delay a bit to enter password after you restart your iphone, then you will meet this bug. The only fix is: Don't use the password protection or when you use the pass word protection, use fastest speed to enter the password once your phone restart it, then you will skip this issue.
There is another way to fix if you meet this bug: If your location service not working, TURN OFF the main button of "Location Service" then turn it back on after few seconds, your location service will be work again.
IT'S REALLY A WIRED BUG AND VERY ANNYOING. HOPE APPLE WILL FIX IT SOON!