iBetaDownload is not responsible for what may happen to your device as a result of using anything listed on our website. Download and utilize at your own risk. iOS 7 is supported on the iPhone 4, 4S and 5, the iPad 2 – 4, and Mini, and the iPod touch 5.
How to extract a DMG on Windows:
1、Get your UDID registered from any reputable source；
2、Download iOS 7 from iBetaDownload website；
3、Plug your device into your computer, and make sure to back it up；
4、Hold Shift (Windows) or Alt (Mac) and click ‘Restore’ in iTunes；
5、Select the iOS 7 file and wait for it to restore；
6、Enjoy! Make sure to regularly update to the new betas that come out.
這裡提供一份“How to extract a DMG on Windows”的視訊教程，有需要的使用者可以下載下來看看！點選直達