iOS 5 beta 4 (Windows / Mac) released for developers and luckily we have found the link to download no matter if you don’t have Apple developer account. Apple also made a release to iTunes 10.5 beta 4 for both Windows and Mac platform, as iTunes 10.5 beta 4 is necessary to upgrade your device with iOS 5 beta 4.
We recommend you, before updating iTunes 10.5 beta 4 make sure your device is running under previous version of iOS 5 beta 2, because once you have updated your iTunes 10.5 beta 4 which will not support your current iOS i.e. iOS 5 beta 2
Note: iTunes 10.5 beta 4 only supports iOS 5 beta 3 and beta 4
Below are the available links to grab your iTunes 10.5 beta 4:
Download iOS 5 Beta 4 [Select your device]