Messaging app provider Line Corp. reported a group net profit Wednesday of ¥5.32 billion ($51 million) in the January to September period, helped by growth in users and advertising revenue.

Line's consolidated operating profit came to ¥18.29 billion on sales of ¥103.24 billion, up 17.2 percent from a year earlier. Although Line expects revenue from advertising and other services to grow in the current quarter through Dec. 31, it did not disclose its full-year earnings outlook, citing uncertainty in the mobile application market.

Line went public both in Japan and the United States in July, in the largest initial public offering in the tech sector this year. Users of its popular messaging app Line can send texts, pictures and stickers — illustrated icons they can buy online. Line also offers in-app sales of games and music.

The number of active monthly users came to 220 million in September, up 3.5 percent from the same period last year. In Line's core markets of Japan, Taiwan, Thailand and Indonesia, that number rose 17.6 percent to 162 million.

Advertising revenue marked a 72.2 percent year-on-year increase to ¥31.42 billion.

Sales in the communication segment that sells stamps grew 6.2 percent to ¥22.32 billion, and content sales that include games were down 9.6 percent to ¥34.02 billion.

Line has been trying to bolster its business both at home and abroad and woo new users at a time when competition is raging with foreign rivals. More than 70 percent of Line's sales came from Japan in the reporting period.

In September, Line entered the mobile phone business in Japan by offering cheap smartphone services, fueling competition with existing carriers and newcomers including retailers.