With more than 1.5 billion users, WhatsApp is the world's most used messenger app in the world. But, lately, it is facing a lot of competition from rivals such as Telegram, Signal and Snapchat who are bringing in more features to offer better user experience.

Adding woes to the Facebook-owned company, the messenger app was caught napping. It recently was panned for serious security loophole, which helped Israeli spy agency track human rights activists and journalists using the Pegasus tool. 

However, WhatsApp is not giving up just yet, as it plans to roll-out new features including the popular dark mode, disappearing messages feature and more. But mobile phone owners won't be able to enjoy WhatsApp with seamless user experience if they are still hanging on to their old devices with the outdated mobile OS.

Read more | Pegasus can spy on multiple people simultaneously

In an advisory to old phone users, the company has said that WhatsApp will stop working on all Windows-powered mobiles after December 31, 2019. That means people won't be able to send images or texts on their phones from January 1, 2020.

As far as the Android version is concerned, it has given a little breather, but only for two months. WhatsApp won't support v2.3.7 Ginger OS and older after February 1, 2020. Thereafter, it will only work on Android 3.0 Honeycomb and later versions.

Must read | WhatsApp dark mode almost ready

On the other hand, WhatsApp will stop working on iOS 8 and older versions from February 1, 2020. After that, it will work only on iPhones and iPad with iOS 9 and later versions.

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