There's a bug in OS 4.1 that has broken location services for some iPhone apps ( https://devforums.apple.com/message/306250 ). Basically location services fails to turn on, and doesn't even ask the user for permission to get their location. The worst thing about the bug is that it doesn't occur when you're installing the app to a device from XCode, it occurs you when you're downloading from the App Store! This makes it almost impossible to test for a fix.
Not everyone's app has been affected, so I'm trying to find out what causes it.
Does anyone have any location services code that's NOT affected by this problem? In other words, who has code for an app that has location services working fine on OS 4.1 devices, when installed from the AppStore?
Thanks!
Tristan
I have found a workaround-Solution: Reset the location warning. (Settings > General > Reset > Reset Location Warnings)
I have seen this occur with apps I have developed when the device has installed a testing version provisioned under a distribution profile and then installs the final version submitted to the app store. The symptom is that Location Services never seems to initialize or ask for permissions and you wind up never being called back with a location or an error to handle.
We have verified that rebooting the device does NOT fix it, but that resetting the location warnings does. In our testing, this only affects devices that ran developer provisioned builds and not 'pristine' devices that only install the App Store build.
I worked through this with the apple help people. Resetting location warning didn't work. Resetting the network didn't work.
Basically, I reset the phone in itunes and set it up as a new phone. The location now works.
来源：https://stackoverflow.com/questions/3852028/iphone-location-services-code-that-works-on-os-4-1-in-appstore