Apple's new firmware update for the iPhone 4 is designed to fix the device's buggy proximity sensor, which is supposed to deactivate touch screen controls when the user hold the phone to their ear to make a call.

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Many users are reporting that iOS 4.1, released Wednesday, does indeed fix the issue. But others who have downloaded and installed the update say their iPhone 4's touch screen still fails to shut off when they hold the phone close to their face.

"Well, it's early days, but the proximity sensor seems improved," user Allan Macdonald wrote Wednesday, on a support forum maintained by Apple. "I have made a few calls with no mutes/speaker on/off issues. Screen goes blank about an inch from my face and comes back on about two inches away," said Macdonald.

Another user, cristianro, said the iOS 4.1 update did more than fix the proximity sensor. "Proximity works great here. Also, more snappy (no more lag in applications), louder speaker. iPhone 4 is the best phone on the market now," said cristianro.

But others said they were still experiencing the proximity problem despite upgrading to iOS 4.1. "It does exactly what it did before," wrote user iphone46187. "The screen comes on even with the proximity portion of the phone mashed into my ear," wrote the frustrated user.

On balance, however, the posts on Apple's support forum indicated that, for the majority of users, iOS 4.1 appears to resolve the proximity sensor bug.

Beyond bug fixes, iOS 4.1 offers a number of enhancements over the original iOS 4.0. It adds the Game Center social gaming platform, 99 cent TV show rentals through iTunes, and social music app iTunes Ping, which lets users track what songs and artists their friends are listening to.

iOS 4.1 also adds High Dynamic Range (HDR) photography to the iPhone and iPod touch. The HDR feature lets users capture a wider range of light intensity and can combine multiple exposures into a single image.

iOS 4.1 is compatible with iPhone 4, iPhone 3GS, and iPhone 3G, as well as the second, third, and fourth generations of iPod touch.

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