Facebook and its Messenger app will stop working for a number of smartphone users by the end of March.
The social media giant has announced it is ending support for devices running some older versions of the apps, including v55 of the Facebook app and v10 of Messenger on Android.
It also announced it was stopping support for Facebook for Windows Phone.
If you find you are suddenly unable to run either app, Facebook suggests updating to the latest version, or migrating to Facebook Lite, a pared down version of the platform.
If your mobile does not support the latest versions of Facebook, the company recommends going to Facebook.com through your mobile browser.
Defending its decision to end support for older versions, Facebook said in a blog: “Our team spends countless hours making it the best way to message your friends and family.
“One of the ways we continue to improve is by consistently introducing rich features, like voice and video calling, games, and bots for Messenger. Using older versions of apps means that experiences won’t work well or sometimes not at all.”
The company says it has “reached out” to those affected and is also offering suggestions in Messenger to people about to lose access.
The full list of devices about to lose support from Facebook includes: v55 of the Facebook app and Messenger v10 on Android, Facebook for iPad v26, Messenger v8 for iOS and Facebook for iOS released in 2011, Facebook for Windows Phone, Messenger for Windows Phone 8 and 8.1, and Facebook for Windows 8 and the 8.1 desktop app.