How Do I Install iOS on My iPhone 4?
Contents Plug Your Device into Power and Connect to the Internet with Wi-Fi. Go to Settings > General, Then Tap Software Update. Tap Install Now. If You See...
Plug your device into power and connect to the internet with Wi-Fi. Go to Settings > General, then tap Software Update. Tap Install Now. If you see Download and Install instead, tap it to download the update, enter your passcode, then tap Install Now.
Can iPhone 4 be upgraded to iOS 10?
Like the older iPhones, such as the iPhone 4 or 3S, you can still use it with the latest iOS version it supports. But if you want the new features of iOS 10, you will need to get an iPhone 5 or newer.
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Can I Install latest iOS on iPhone 4?
The iPhone 4 does not support iOS 8, iOS 9, and will not support iOS 10. Apple has not released a version of iOS later than 7.1. 2 that is physically compatible with an iPhone 4— that being said, there is no way for you to “manually” upgrade your phone— and for good reason.