Apple is taking a harder look at complaints that the latest version of its iPhone software is burning through battery life at a fast rate.

The iPhone OS 3.1 software added numerous new features like application recommending, improved Exchange support, and access to a ringtone store, but multiple users are reporting it significantly increases power consumption. AppleCare specialists have sent follow-up questions to an undisclosed number of iPhone owners who posted on its support forums about the decreased battery life.

"My battery life has been cut in half," said poster "SafeData1" in Apple's support forums. "I have tried the restore and would like to go back to 3.0 until Apple resolves problem."

Some users are also complaining that the latest version of the firmware is causing problems while trying to log in to Exchange 2007 server accounts, particularly while using an iPhone or iPhone 3G. Apple said this occurs because the software correctly identifies whether the device has hardware encryption or not, and some Exchange servers require this for access. The iPhone 3GS comes with hardware encryption, and other iPhone owners need to contact IT administrators to configure Exchange access for older iPhone devices, Apple said.

Other users are also reporting minor issues with sluggish performance, podcast playback, and random shutdowns with the 3.1 software. Apple suggested users may be able to fix these issues by resetting the device by holding down the home and sleep button until the Apple logo appears. The company also said performing a full restore with iTunes may also fix these nagging issues, but it recommends backing up the device first because it will erase much of the user's iPhone data.

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