WhatsApp is set to stop working on 47 phone models in the UK from January, potentially affecting millions of users.
People using old iPhone and Android models will need to upgrade in order to use the app after December 31.
There will be a warning message before the app ceases to work on certain phones, with the change affecting models like the iPhone 5, as well as Samsung, Huawei and LG.
A statement from WhatsApp explaining the move said: “Devices and software change often, so we regularly review what operating systems we support and make updates. These devices also might not have the latest security updates, or might lack the functionality required to run WhatsApp.