Millions of people may be unable to use WhatsApp on their phones as of today, November 1.

The messaging platform will cease to function on many Android devices as well as Apple’s iOS devices. Users’ messages, photos, and contacts may be lost.

According to Facebook, which owns WhatsApp, the messaging platform will not support smartphones running Android 4.0.3 or lower.

In Apple’s case, the limit has been set at iOS 9 or lower.

How to Determine Whether WhatsApp Support Has Ended on Your Android Device

1. Go to Settings > About phone.
2. Scroll down to look for the Android version running on your device.
3. If it’s Android 4.0.4 or lower, you should look to switch to a device with a higher version of Android.

The following smartphones will lose access to Whatsapp today, November 1

Android Phones:

LG: Lucid 2, Optimus F7, Optimus F5, Optimus L3 II, Dual Optimus L5, Best L5 II, Optimus L5, Dual Best L3 II, Optimus L7, Optimus L7, Dual Best L7 II, Optimus F6, Enact Optimus F3, Best L4 II, Best L2 II, Optimus Nitro HD, Optimus 4X HD and Optimus F3Q.

Sony: Xperia Miro, Xperia Neo L, and Xperia Arc S.

Samsung: Galaxy Trend Lite, Galaxy Trend II, Galaxy SII, Galaxy S3 mini, Galaxy Xcover 2, Galaxy Core, and Galaxy Ace 2.

ZTE: Grand S Flex, ZTE V956, Grand X Quad V987 and Grand Memo.

Apple iPhones:

iPhone 6, iPhone 6s plus, iPhone SE