Erick Guo left Asia's largest Internet company last year to build a team of artists and engineers who could create smartphone applications inspired by Japanese comics. The 25-year-old and his team ended up with China's hottest app last month and are working on their next hit.

The free app, called MYOTee, lets people design avatars, or digital images, of themselves and friends that can be used for instant messaging or on social networks. It soared to the top of the Apple Inc and Google Inc Android app stores in China in June, with its software downloaded 36 million times.

Guo, who had previously worked at China Web giant Tencent Holdings Ltd, developed the app by inviting Hong Kong T-shirt artist Peter Lee to join the team and create digital versions of his designs. With backing from venture firms such as IDG Capital Partners, Guo's team at Lemon Tech is now seeking to follow up MYOTee's success with other new products such as mobile games.

"We hope to become the youth market's favorite technology company," Guo said in an interview via instant messaging.

MYOTee, known in Chinese as Lianmeng, lets people customize cartoon images by choosing facial features, hair color and accessories like hats or sunglasses.

What has helped it gain momentum is that the avatars can be used across social media, such as Tencent's WeChat messaging service, which has about 400 million users.

The avatars, with designs similar to Japanese manga comics, lend a more intimate, playful feel to messaging over smartphones and other devices.

"The style of it, being very cute, is a cultural thing here because we grew up watching Japanese animation," said Yan Yan, who tracks new Chinese businesses as the Shenzhen director of entrepreneur community Startup Grind.

Although an early version of MYOTee was released in December, it did not really take off until May, when a redesign brought an easier-to-use interface and changes to characters.

MYOTee overtook GameLoft SE's Rival Knights for the top spot in the Apple store on June 9, according to Distimo, an app tracker. Later that week, MYOTee passed Tencent's QQ instant message app to lead the larger Android market.

Among those won over are Stacey Yu, who works for a government agency in Hangzhou.

The 27-year-old likes how interactive and easy-to-use the app is, and she said she has shared it with about 10 people, including her parents.

"A friend recommended it to me, and I think it's a lot of fun," said Yu, showing off avatars that include a girl with bunny ears and a man with a fishing rod.

"My father creates around seven avatars a week, one for each day."

Guo's challenge now is to make sure his company avoids becoming a one-hit wonder, like so many app developers before it, said Yan. Though MYOTee doesn't generate any revenue, Guo has a bit of a cushion because of the venture capital backing.

"They have enough time to decide where they want to go," Yan said.

Guo and his Shenzhen-based team have tapped into a formula that has proved popular in China: borrowing an idea from overseas and customizing it for local tastes. Sina Corp's Weibo service is similar to Twitter, while 58.com Inc is a Craigslist-like site for China.

MYOTee is similar to Bitstrips, a Toronto-based company founded in 2007, which focuses on full-length avatars with backgrounds and scenery.

MYOTee concentrates on close-ups, emphasizing combinations of facial features and accessories.

Guo said it was a love of Japanese comics that lured him away from Tencent, a Shen-zhen-based company that develops software for mobile messaging, advertising and games. He admits he is not much of a designer, so he depends on his startup's four artists, including Lee.

"I love Japanese manga, especially One Piece," he said, referring to the popular series centered around pirates.

Guo said their goal of 10 million downloads for the whole year was ambitious because they wanted to motivate their team. They hit the 36 million mark by the end of June, he said.

After securing funding from IDG Capital Partners earlier this year, the team's goals are growing, with talks underway for a second round of financing, Guo said. He declined to say how much they plan to raise or with whom they are talking.

The funds will be used to double the team to about 20, helping them develop new products such as mobile games and social comics in the coming year, he said. IDG Capital did not reply to two e-mails sent to its Beijing team.