Apple has given developers an access to download iOS 5.1 beta (build 9B5117b), the latest development step for Apple to address battery issues besides offering stability improvements over iOS 5.0.1. Xcode 4.3 has also been pushed out for compatibility.
With iOS 5.1, details are scant right now. No new feature has been spotted nor called out by Apple in the change log. But, developers have already started digging a little deeper into iOS 5.1 beta rigs. Numerous bugs have been reported by iPhone users. We would recommend you to be cautious and take a backup before you install iOS 5.1 beta on your iPhone, iPod touch or iPad.
Developers looking to have their Apps updated before iOS 5.1 is available for download can head to the Apple Developer site ($99/year Developer Program required) and download the iOS 5.1 beta 9B5117b for iPad (3G, WiFi), iPad 2 (3G, WiFi), iPhone 4S, iPhone 4 (GSM, CDMA), iPhone 3GS, and the 3rd and 4th generation iPod touch models.
In case you are not registered, you can still follow the direct links listed below to download bits of iOS 5.1 right now.
Download iOS 5.1 BETA direct links
iPhone 4 (GSM)
iPhone 4 (CDMA)
iPad 2 (Wi-Fi)
iPad 2 Wi-Fi + 3G (GSM)
iPad 2 Wi-Fi + 3G (CDMA)
iPad (Wi-Fi and Wi-Fi + 3G)
iPod touch (4th generation)
iPod touch (3rd generation)