But although he's left the company, Knott-Craig has described Mxit as Africa's biggest tech success story -- and one he believes will continue to grow.

CNN: Mxit: South Africa's Facebook beater

Through its own standard protocol, Mxit subscribers can also connect to other social networks and instant messaging applications such as Facebook, Google Talk, Yahoo, AIM and ICQ.

FORBES: Top 20 Tech Startups in Africa

So how does Mxit make money?

CNN: Mxit: South Africa's Facebook beater

Then there is innovation in social and communication companies such as Mxit, which is a mobile communication platform across all types of devices, and if you listen to its new CEO Alan Knott-Craig Jnr, it is well on its way to "conquering the African market".

CNN: STORY HIGHLIGHTS