Millions of smartphone users will need to upgrade their mobiles to keep using WhatsApp in the New Year.

The Facebook-owned company has announced it is updating its software to keep pace with new technology, meaning the messaging app will no longer work on older devices in 2017.

A spokesperson said: "While these mobile devices have been an important part of our story, they don't offer the kind of capabilities we need to expand our app's features in the future.

"As we look ahead to our next seven years we want to focus our efforts on the mobile platforms the vast majority of people use."

The company has set a deadline of the end of 2016 for several older services that will no longer be supported.

Will you be affected by the upgrade? Here's what you need to know:

iPhone users

WhatsApp will stop working on any iPhone 3GS, the second generation handset that was released in 2009.

It will also stop being supported on any device running iOS 6. Any iPhone 4, 4S, or 5 that doesn't have the newest version of the operating system - iOS 9.3 - will need to be updated.

To check which version of iOS you have go to Settings, then General and then Software Update.

First, second, third or fourth generation iPads also need to be updated.

Android users

Phones or tablets running Android 2.1 or 2.2 won't be supported after the end of the year. This covers devices released between May 2010 and November 2011 from many different manufacturers.

Android's latest version is 7.0. Check what version of Android you're running in the Settings menu.

Windows phone users

WhatsApp is set to drop its support for Windows Phone 7, which was released worldwide in 2010. Users should upgrade as soon as possible.

BlackBerry and Nokia users

You're in luck. WhatsApp had been planning to drop support for BlackBerry OS, BlackBerry 10, Nokia S40 and Nokia Symbian S60 at the start of 2017 but has announced it will extend its support for the devices until June 30.