Less than four years after Line’s launch, the company says that more than 560 million people worldwide have registered as members, the majority of them in Japan, Taiwan, and Thailand. One hundred eighty one million users log in to the Line app each month. While that’s a smaller user base than WhatsApp (700 million monthly active users according to research firm Canalys), Facebook Messenger (500 million), and Tencent’s WeChat (480 million), Line has done a remarkable job of turning its popularity into a growing, diversified business. ... Its reported revenue of $656 million in 2014 comes from a range of sources that few rivals can match: It sells games that can be played solo or with other Line users; those digital stickers, which can be purchased to express a dizzying array of emotions; marketing deals with brands and celebrities that want to reach its user base; and merchandise such as the products at the Harajuku shop. ... Spy on other passengers in the Tokyo subway, and there’s a more-than-decent chance that you’ll spot a salaryman or schoolgirl interacting on their smartphone with Brown, Cony, or one of the app’s other hyperlovable mascots. Visit a restaurant and a small placard at the cashier invites you to follow the business on Line in return for discounts. On billboards, the characters endorse chewing gum. Visit an electronics store and you’ll find them in plush form, as prizes in a coin-operated crane game. ... "The turning point," Idezawa says, "was when we released stickers." ... The Japanese call cuteness kawaii, and find it surprisingly meaningful. "The word ‘kawaii’ in Japanese literally means ‘acceptable of affection’ or even ‘possible to love,’" explains Kotaku’s Ashcraft, who says that it’s used to refer to everything from babies to dogs to clothing. Kawaii imagery is "used to soften things, making them more palatable and even more friendly. That's a reason why it's not uncommon to see cute characters in everything from public safety posters to home-loan brochures."