The trick is that Facebook Zero is free, benefiting from what’s known as zero rating by the phone companies. Accessing it doesn’t rack up any data fees, which are a big deal in emerging markets, where almost everyone is on a prepaid plan. (In countries in the developing world, the average monthly spend on mobile connectivity, which is often just voice and text, is 8-12% of the average take-home pay of a cell phone user, says Nathan Eagle, CEO of opt-in mobile ad network Jana.)
In the 18 months after Facebook Zero launched in Africa, the number of Africans on Facebook ballooned by 114%. It’s hard to directly link that growth to Facebook Zero, but it’s easy to see how they could be related. (In the 10 months since then, the number of users of Facebook in Africa grew only 18%.) In Kenya, which is typical for the continent, 99% of access to the internet is accomplished on mobile devices, almost all of which are either feature phones or even more basic models capable only of voice and text messaging. Facebook is now so popular in Africa that the site is driving the adoption of broadband internet, just so users can have faster access to all those pictures and status updates. [link]
Source: The one reason a Facebook phone would make sense http://qz.com/69163
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