The app's main competitor in Japan will be Uber, which had a limited launch in Tokyo in November 2013 before expanding to a full service last March. British taxi app Hailo is also available in Japan in the cities of Osaka and Tokyo. As noted by TechInAsia, this limited activity makes Japan a relatively tranquil market for taxi apps — especially compared with the rest of Asia, where there are as many as 10 apps battling it out in a single country. TechInAsia adds that in its own comparison of Line Taxi and Uber, it was Line that offered "better coverage and shorter wait times" for cars in central Tokyo.

Line's taxi app features its ever present retinue of cartoon mascots. (Line)

The launch of Line’s taxi service underscores the company’s growing ambition. Like rivals WhatsApp, KakaoTalk, and Kik, Line has ridden the free smartphone messaging boom to reel in tens of millions of users (the company boasted 170 million monthly active users as of October 2014). However, four-year-old Line has been quick to expand beyond messaging and now has a family of mobile offerings including games, antivirus software, drawing tools, a camera app, and Line Pay. Arraying these apps around a central messaging service has so far proved to be a smart strategy for Line — but can a little messaging with friends help it take on the behemoth that is Uber?