Line, a popular alternative text messaging service that originated in Japan, has now become one of the biggest players in this space alongside services such as WhatsApp and Viber, with 85% of its users now being outside of Japan. WhatsApp was recently acquired by Facebook (NASDAQ:FB) for the shocking sum of $19 billion. Now, Bloomberg is reporting that Line is making a big push toward 1 billion users sometime within 2015, which could represent fierce competition for Facebook's expensive new acquisition.

In this segment from Tuesday's Tech Teardown, host Erin Kennedy and Motley Fool tech and telecom bureau chief Evan Niu discuss the rapidly growing message service business, and just how tough the competition here could possibly get. Line currently stands at around 400 million users, with WhatsApp at around 450 million, both with their eye on that 1 billion benchmark. But the message service business isn't a terribly sticky one, with little keeping users from switching over to whichever app is the most popular. If Line ends up cutting into WhatsApp's growth and stealing those users for itself, this could represent a definite risk for Facebook's extremely expensive acquisition.

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