TV series "bref." (CANAL+) follows an anonymous 30-something stumbling through life. The show was a hit among 20- and 30-somethings in France, but ended after one season.

Challenge: how do you maintain a cult following once a hit's off the air?

Solution: Give fans the first-ever app that lets them call their favourite characters from the show.

The "bref." app puts you in control of the hero's phone. In addition to skimming his photos and playing with his smartphone apps (featured on the show), you can read his texts ... and CALL HIS FRIENDS! This was the best feature: each "bref." star was given a cell phone whose number appeared in the phone book. When fans called a show character, they actually picked up, spending up to one hour talking with their fans!

Fans were blown away: they tweeted, blogged it, videotaped themselves making calls, and freaked out -- yielding over 500,000€ in earned media coverage. In 24 hours, "bref." was the top free app in the French iTunes Store. In a week, it got over 100,000 downloads. Three months later, the figure mushroomed to 750,000. It continues to hold a 5-star average rating.

All this was accomplished with ZERO media budget. App development was sponsored by credit provider Sofinco, who loved the exposure to this demographic. Most importantly, it made lots of happy "bref." fans – many of whom spent up to an hour on the app at a time, reliving "bref." through this incredible handheld window.