In a recent blog post, WhatsApp, the popular Facebook-owned instant messaging app, announced a significant change that will affect millions of users worldwide. The company revealed that it will be withdrawing support for several outdated mobile platforms, including BlackBerry devices (even the BB10 version), Nokia’s Symbian 40 and 60 versions, Google’s Android 2.1 and 2.2, and Windows Phone 7.1. This…