Download iOS4 4.1 IPSW
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By updating iPhone OS to iOS 4.1, it will update the baseband version to the latest 05.14.02 (3G and 3GS) / 2.10.04 (iPhone 4) basebands.
Download iOS4 (4.1) IPSW for Apple iPhone 4/4G, iPhone 3GS, iPod Touch 2G, iPod Touch 3G and iPod Touch 4G directly from Apple’s server.
If you don’t know how-to install iPhone firmware to your iPhone, read this guide: How-to Update iPhone firmware Shift + Restore method
Download iOS4 4.1 IPSW for iPod Touch 2G
Download iOS4 4.1 IPSW for iPod Touch 3G
Download iOS4 4.1 IPSW for iPod Touch 4G
Download iOS4 4.1 IPSW for iPhone 3G
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