When the next iPhone is released this year, older models will no longer receive software or security updates and some apps will no longer work.
The iOS11 operating system will not support the iPhone 5, 5c or iPad 4 - meaning that these products will be stuck on iOS10, leaving them without the latest updates.
These devices were built on 32-bit architecture, but the company has now completely switched to 64-bit architecture, The Independent reports.
This means that games or apps which run on 32-bit will no longer work.
New iPhones are set to be released later this year and iOS11 is expected to be made available around September.
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