"App store update kills all older phones.: App Store update on IOS 16. I had a need to install an app on my Iphone X, OKTA. I went to my app store button and it now tells me I need IOS 18, but the Iphone X will not update past IOS16. This update kills my phone and its functionality. I am unable to access the app store at all. This is a major issue for me and my wife, it impacts her Iphone as well."
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Thank you for the screenshot.
It's Time for a New Phone:
It is a different version (6.6) that is provided here. You iPhone model (X) is just not compatible, because it does not meet the minimum system requirements. As result, you need to upgrade to a much newer model. It still wokrks, but may app are just inaccessible.
Apple's 7-Year End of Support:
Apple is proprietary, in that they make their own calls --and about every 7 years after a device's release date, Apple has a tendency to discontinue updates for the device, thereby making it no longer supported, or with limitations. It's how Apple keeps its customers up-to-date with one another. Why 7 years? Got me! But, Microsoft and Android are much different, in that they make their own change --MS Office versions 2016 and 2019 were discontinued one the same date, but in a three year different timespan. See here: End of support resources for Office | Microsoft Support