How to uppdate iOS on iPhone 6 beyond iOS 12?

Hello ~ You can update to iOS 12.5.7 but no further. Click on the links below….

Update your iPhone or iPad - Apple Support

If your iPhone or iPad won't update - Apple Support

If you need a higher version of iOS you will need a newer iPhone. Click below to shop for a new device…

iPhone - Apple Official Site

If you purchase a second hand device please take a moment to read these helpful links by clicking on below to make an informed decision…

Activation Lock for iPhone, iPad, and iPod touch - Apple Support

Also:

The All Too Common SAD Reality of Buying a Used iPad/iPhone

~Katana-San~

... and you won't be able to upgrade it past that version as it does not have the necessary hardware to support any newer iOS versions. If you need to run apps, that require a newer version of iOS, you will have to get a newer iPhone model.

An iPhone 5s or iPhone 6 isn't capable of 13 or above; they require at least 2GB of RAM. If you're trying to install 12.5.7, describe what happens.

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