WhatsApp will cease support the older mobile platforms such as all versions of BlackBerry OS (including BlackBerry 10), Nokia S40, Symbian S60, Android version 2.1 and 2.2 and Windows Phone 7.1 by the end of 2016 . These mobile devices running older operating systems do not have the capabilities to offer support for upcoming features.

This means those users who are using the affected mobile platforms, need to upgrade their devices to newer version of Android, iPhone or Windows Phone before the end of 2016 in order to continue using WhatsApp.

"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," WhatsApp noted in its official blog post, "This was a tough decision for us to make, but the right one in order to give people better ways to keep in touch with friends, family, and loved ones using WhatsApp."

The announcement comes just after WhatsApp turned seven years old. Launched in 2009, the cross-platform instant messaging service recently hit the milestone of one billion users. The company also promises to include more security features.

"We are proud of this milestone, and we're humbled by the extraordinary ways all of you have used WhatsApp," the company said upon its success, "So even as we celebrate this achievement, our focus remains the same. Every day, our team continues to work to improve WhatsApp's speed, reliability, security and simplicity. We're excited to see how far we've come. But now, it's back to work – because we still have another six billion people to get on WhatsApp, and a long way left to go."