Is background GPS\location logging possible on iPhone 4 or 3GS running on iOS4

I've never coded anything for the iPhone but have written a GPS tracker for Windows Mobile,开发者_JAVA技巧 with the release of iOS4 I understand there have been some improvements to the multitasking story.

Is is possible to log a GPS trail with an app running on the iPhone iOS4? Can you achieve this by running in the background or using scheduled push notifications to wake up the app, or some other way?

Also, if the above is possible, is it possible to transmit the GPS trial in the background with a web call etc.

Yes IOS4 allows your app to log GPS trails in the background. See the Apple docs for more info http://developer.apple.com/iphone/library/documentation/iPhone/Conceptual/iPhoneOSProgrammingGuide/BackgroundExecution/BackgroundExecution.html#//apple_ref/doc/uid/TP40007072-CH5