"The smartphone is a social platform in ways that the desktop computer never really was," Evans said. "A lot of the winner-take-all dynamics don't apply on the smartphone."
Facebook has been adjusting to this reality more quickly than many other Internet companies that began to thrive while PCs still ruled. While Facebook remains the world's most popular hangout with 1.23 billion users worldwide, a lot of its audience turns to other mobile apps for reading news, sharing photos and sending messages.
The fragmentation is prompting Facebook to develop a suite of discrete apps. Besides acquiring Instagram for sharing photos on mobile devices, Facebook recently introduced a new app for perusing news and now is trying to become a bigger player in mobile messaging with the WhatsApp acquisition.
Facebook is "trying to keep its coolness factor with all these different products that could turn them into a mobile media conglomerate," said Virginia Commonwealth University journalism professor Marcus Messner, who studies social media.
Facebook already offers its own messaging app tied to its social network. Although that app is popular in its own right, Zuckerberg noticed that it increasingly had become more like email instead of real-time communication like WhatsApp is. Most WhatsApp users also give the service access to the personal contact lists stored on smartphones, providing Facebook with another potentially valuable source of data.
"This is not an investment in the current value of WhatsApp," Messner said. "This is an investment in the potential of WhatsApp."
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