2. WhatsApp
WhatsApp is an instant messaging app for smartphones that operates under
a subscription business model. The proprietary, cross-platform app uses the Internet to
send text messages, images, video, user location and audio media messages.
In January 2015, WhatsApp was the most globally popular messaging app with more
than 600 million active users.
In April 2015, WhatsApp reached 800 million active users.
WhatsApp Inc., based in Mountain View, California, was subsidized by Facebook on
February 19, 2014, for approximately $16 billionUSD.