<p style="text-align: justify;">WhatsApp, the massively popular messaging app owned by&nbsp;FacebookInc.,&nbsp;is adding video calling to its smartphone app across three operating systems: Apple Inc.&rsquo;s iOS,&nbsp;Alphabet&nbsp;Inc.&rsquo;s Android andMicrosoft&nbsp;Corp.&rsquo;s Windows smartphone OS.</p> <p style="text-align: justify;">With cross-platform video chatting in place, WhatsApp is offering a combination of video and text messages in one app, similar to what is found in Microsoft&rsquo;s Skype, Snap Inc.&rsquo;s Snapchat and Facebook Messenger. Chatters won&rsquo;t have to wonder what OS their friends are on when they go to chat face to face. (The software also competes with Apple&rsquo;s proprietary FaceTime and Google&rsquo;s Duo app for iOS and Android.)</p> <p style="text-align: justify;">The launch Tuesday&mdash;in an app update for iOS 8 or newer, Android 4.1 or newer and both Windows 10 Mobile and Windows Phone 8.1&mdash;will bring video calling to over 1 billion WhatsApp users across more than 180 countries on the same day, said&nbsp;Manpreet Singh,WhatsApp&rsquo;s lead engineer.</p> <p style="text-align: justify;">Like Apple&rsquo;s FaceTime and iMessage apps, WhatsApp offers a security feature called end-to-end encryption that&rsquo;s turned on by default for text, voice and now video messaging. End-to-end encryption means the transmission is encrypted even on WhatsApp&rsquo;s own servers, so it would be equally obscured from hackers and government agencies, and would be hard for WhatsApp to divulge, even with a court order.</p>