How to update ios on 8.0

Update the iOS software on your iPhone, iPad, or iPod touch - https://support.apple.com/HT204204

The iPhone 4 can not run anything higher than 7.1.2

If you have an iPhone 4, it can’t be updated past 7.1.2.

If you have a newer iPhone, update it to 9.3.5, 10.3.3, or 11.2.6 depending on what model it is through the Software Update function or iTunes on a computer.

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