As chat apps evolve to become platforms, a social network for couples is also embarking on the same route.

VCNC, the company behind Between, an app that originated from South Korea for couples to share their moments in a private social network, has just landed a strategic investment from billion-dollar Japanese mobile games firm DeNA. VCNC notes that the investment, which is of an undisclosed amount, “will be made to form a business alliance to grow Between into an open platform and later support the opportunities to monetize Between.”

The move hints that an array of other services including mobile games and e-commerce, which DeNA is best known for, could soon land on Between as it seeks to make money from its platform for couples.

In an indication of such plans, Between has already been working with a variety of industries, including restaurants, movies, jewelry, wedding, travel, baseball teams and so on through its current channels — “Event Box” and “More Tab” — as it seeks to make such third-party purchasing services available to its users.

Between 2.0, the first major update released in December since the app’s official launch in March last year, also features a shared calendar so users can plan their dates, and keep track of special events such as birthdays or anniversaries. Cue the entrance of e-commerce opportunities.

en2 iP5 Between, the social network for couples, cozies up with Japanese mobile games firm DeNA

Between co-founder Edward Lee says, however, that there aren’t any specific details to share on what DeNA will be working on together with VCNC, though he believes that they can “receive support with growth in Japan” — which is Between’s second-biggest market after its home turf of South Korea — as well as get “help on how Between should monetize.”

Our goal is to make Between a platform, where third party services can help us add value to our users…

We will continue to work with other businesses and think of many other ways to provide for couples. And to do this we need more development resources, which is where we plan to execute our investment.

Between 2.0 marked one of the company’s strongest pushes to grow its global userbase, but it is facing stiff competition.

Y Combinator-backed Pair arrived on the scene in March 2012. It won investment from Path founder Dave Morin, SV Angel, Crunchfund and others, going on to acquire UK-based Cupple and rebrand to Couple — another competitor is Avocado, which was started by ex-Googlers. Equally private social networks like 23snaps and Everyme cater for select groups, which could range from friends and extended families, to couples.

Lee notes that it may be “difficult” for Between to scale so rapidly like the way Facebook and WhatsApp have done so — since it does not have a “network effect” like them.

However, he also observes that there is a “great scaleability in the business aspect, since this segment has the highest spending.”

Isao Moriyasu, the president and CEO of DeNA, says that “purpose-specific social networks like Between are rapidly gaining popularity worldwide, following the massive adoption of general social networks and communication tools.”

DeNA started off with games on mobile browsers and found success monetizing its service with virtual items and other tactics, but it has struggled to adapt to the dominance of app stores, which smartphone owners worldwide now use to access mobile content.

The company is therefore increasing its focus on new distribution models, such as its mobile messaging app Comm and Japan-only music service Groovy – and manga has become its latest focus. As DeNA seeks such new ways to capture its audience, startups such as ‘themed’ social network Between could very likely help it gain new insights and benefit its own business eventually.

With DeNA’s wide range of services, it will also be interesting to see Between evolve into more than just a private space for couples with this latest investment — there could be much more creativity in terms of commerce and entertainment offerings, for example — and this could just very well help it stand out among the competition it is facing.

Already, the team behind Between says the app has seen a more than two-fold increase in daily user acquisition after its major update in December — and the amount of time spent a month per user has risen to 510 minutes currently, from 300 minutes a year ago. The app has also just passed 5.92 million downloads.

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