Users of key platforms are getting older and mobile platforms are becoming even more dominant.
![The biggest social networks concentrated on mobile platforms in 2013 [EPA]](/wp-content/uploads/2013/09/201392523649783580_20.jpeg?resize=270%2C180&quality=80)
Users of key platforms are getting older and mobile platforms are becoming even more dominant.
This year has seen social media officially become part of mainstream media, but what challenges will 2013 present?