Tokyo-based Flier, a startup that provides book abstract apps under the same name, announced yesterday that it has fundraised an undisclosed sum from East Ventures, Nishikawa Associates, and Nomad.

Since its official launch back in October 2013, the company has acquired over 20,000 users, more than double the 9,000 users as of March 2014. According to the company’s CEO Yasushi Ohga (former CTO), Flier will use the funds to hire engineers and strengthen their in-house engineering capacity.

Flier was launched back in June 2013 and graduated from Tokyo-based incubator Movida Japan‘s seed acceleration program. Their team earned a good reputation from an audience at the incubator’s Demo Day back in November, and had acquired 17 corporate accounts before their pitch at the time.

However, their business is based on a simple concept, so they may soon hit a ceiling in their growth. As they expand their business, they will have to hire more staff, which will drive up in labor costs. In a response to my question regarding these problems, he explained:

Getabstract has 10 million users, mainly in the US and European regions. The market volume in this space is two million users in Japan, so we still have more room to increase our users. If you look at the Asian market, we can aim to acquire 20 million users in the entire region.

The company has three, full-time writers, and uses about 10 freelance writers to provide over 20 abstracts (for 20 books) every month. They plan to increase it to 50 abstracts every month, but they will use the funds raised at this time not to hire new writers but to strengthen their engineering team to enhance their web service, while details have not yet been disclosed.