Facebook has already admitted that teenagers are leaving its site — and the big question is: where are they going?

In Japan, the answer may very well be TwitCasting, a service that lets you stream and broadcast live videos with your Twitter or Facebook account. This means people can watch your videos as they’re being recorded — or what may be thought of as a Twitter livestream for videos.

The idea behind TwitCasting itself isn’t new — in fact the space is already quite saturated with competitors including Ustream, Hang w/ and qik, which basically offer the same functionalities — but TwitCasting’s focus on teenagers is the differentiating factor that holds a degree of potential for it to gain more traction.

The company behind the app, Moi Corporation, claims that 50 percent of college students in Japan are using TwitCasting currently — that’s about 1.3 million users. “Japanese teens seems to prefer real-time communication service. As you can see, (messaging service) Line has gained so much popularity,” a spokesperson says.

There’s still a long way to go before Facebook should feel threatened though. After all, recent statistics show that Facebook has 21 million monthly active users in Japan.

Meanwhile, TwitCasting has just passed 4 million registered users worldwide, and half of them are teenagers. It took two years to reach 1 million users in April 2012, but just nine months to climb from 2 million users in February to 4 million users now. TwitCasting notes that the app is gaining popularity in South America and East Asian regions.

Outside of Japan, TwitCasting is most used in Brazil — which accounts for 13 percent of its total users. US takes third spot.

TwitCasting Live video app TwitCasting is popular with Japanese teens, and now its targeting the US

Moi Corporation believes there are two main reasons why TwitCasting is seeing success with teens in Japan — first of all, there is a high penetration rate of smartphones, with 84 percent of high school students owning one in the country, and TwitCasting’s livestream capabilities are specially tailored for smartphones. Secondly, the network effect: as the top-ranked users gain tens of thousands of viewers for each broadcast, TwitCasting becomes more addictive for teenagers who want to make themselves known.

To keep a check on teen safety though, the TwitCasting team has some measures in place. Movies and comments are checked by human eyes and user reports, while sexual and violent movies are also double-checked systematically using an external service. The company also cooperates with official organizations such as the Child Exploitation & Online Protection Center in the UK.

The team behind TwitCasting has decided to open an office in Silicon Valley as it seeks to bring this success formula overseas and up its global expansion efforts. A spokesperson tells TNW:

As English is a globally common language, we consider that it is key for us to show presence in (the) English speaking world. US is clearly the epicenter of IT trend, venture funding and English (obviously). Because our service is based on movies, we use a lot of bandwidth. So US’s stable and fairly priced infrastructures are very attractive for us.

As teenagers flock to services that emphasize self-expression, TwitCasting has a shot at appealing to a wider audience beyond Japan. I personally don’t find TwitCasting appealing at all — watching random people setting up a tutorial or performance on live video just isn’t my cup of tea — but if it extends beyond random people to include celebrities who hold performances on it, TwitCasting could become a service to be reckoned with. Already Brazilian singer Ivete Sangalo, who has 9 million Twitter followers, is a regular user of TwitCasting.

➤ TwitCasting Live: iOS | Google Play

Headline image via Yoshikazu Tsuno/AFP/Getty Images

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