Three makes a trend. With Facebook’s announced acquisition of Snaptu today, the Israeli startup becomes the third mobile-related purchase for the company this year after advertising startup Rel8tion and group messaging app Beluga.

Snaptu, which helps developers create smartphone-like experiences on basic feature phones, partnered with Facebook earlier this year to bring the app to 2,500 different kinds of mobile devices. Making Facebook accessible to the most basic of devices in markets outside the developed world is essential if the company wants to grow beyond its existing 600 million users.

It looks like that arrangement went well enough that Facebook decided to buy the whole team. On AppData, the number of Snaptu’s monthly active users have steadily risen over the past several months to 4.4 million. In fact, it’s the fastest growing Facebook mobile client behind Android and iPhone.

Daily actives come in at just under a third of that number at around 1.27 million. The stickiness, or ratio of daily active users to monthly use, is about half of what is typical for Facebook’s smartphone apps for the iPhone and Android. But that’s understandable considering that these are feature phones.

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