Since January 29, Line users have been doubling in Hong Kong. Just 2 weeks before that, Line also passed its 100 million user mark on January 18th.

Line is a Japanese messaging application that provides free calls and chatting. The Japanese arm of the Korean firm NHN developed the app and it has most of its users in Japan, and its Chinese version was launched on December 12 of last year, and it is gaining strong momentum in Asia. It ranked first on the free app category in Thailand, Taiwan, Hong Kong, and Singapore (to name a few).

The increase in the Hong Kong users seems to have been caused by some service provider decisions to impose annual fees on SMS messages. Telcos in Hong Kong charge for inter-network messages in order to gain more users through bringing friends and family on to the same networks.

As early as July 2012, Line got $3.75 million each month in sales - with the current lookout, the number is expected to be higher now, as at February 2013. The difference with Asian messaging apps is that they focus on both voice functions and messaging - WhatsApp, for example, does not support voice calls, whereas WeChat and KakaoTalk do. It will be interesting to see how they will attempt to branch out further to the world in the near future.