Facebook is to buy feature phone app developer Snaptu to further its ambitions in the developing world.
The acquisition, for an undisclosed sum, will allow Faceboook to further target the developing world, where feature phones predominate, and drive further into the mobile market.
Earlier this year Facebook stated that mobile was its top priority in 2011.
Snaptu operates from London but also has offices in Tel Aviv and Silicon Valley. In January Snaptu delivered the Facebook for Feature Phones mobile app.
In a blog referring to the acquisition, Snaptu said: 'We soon decided that working as part of the Facebook team offered the best opportunity of accelerating the pace of our product development.'
This is Facebook's fourth acquisition this year. Earlier it bought messaging pod company Beluga, social networking recruiter Pursuit and ad technology company Rel8tion.
Facebook has also set up collaborations with manufacturers HTC and INQ for Facebook features on a number of phones.