Millions of smartphone users won't be able to access WhatsApp from January 1, 2021, onwards as their devices will no longer remain compatible with the messaging app. WhatsApp has yet again announced that is withdrawing support for certain older devices which are currently compatible with the messaging app.

Some users of older devices will still be able to access WhatsApp by updating to the latest software. However, for some devices, WhatsApp will become permanently inaccessible from January 1, 2021, onwards.

Dropping support for older devices is a regular exercise for WhatsApp. This time it is dropping support for any iPhone running on software older than iOS9. Users with these phones won't be able to use WhatsApp from January 1, 2021, onwards.

The WhatsApp announcement means that the iPhone 4 and models will not be able to access the messaging app from the beginning of next year. iPhone 4S, 5, 5S, 5C, 6 and 6S can all be updated to iOS9, hence they will be able to support WhatsApp once updated.

Android phone users have not been spared either. WhatsApp will no longer work on Android devices running on devices running Android 4.0.3 or older versions of the operating system. If users have such phones that are no longer compatible with WhatsApp then they must back up their chats before January 1, 2021, if they want to retain them.

They can do so by going to 'Chat backup' option under Chats section in Settings. Aside from backing up their chats, users of old devices should also start looking for smartphones that are compatible with WhatsApp if they want to use the messaging app in the future.