According to the official press release, this version is compatible with iPhone 4 for the GSM networks, iPhone 3GS, iPad and iPad 2, iPod touch third and fourth generation.
It is noted that for the iPhone 4 working in networks of CDMA, another version - iOS 4.2.10 (build 8E600) has been released. Recall that the iOS version 4.3.4 was released just ten days ago.
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