The complimenting app Gas has become the most popular among teenagers in the US

Five years ago, TBH, an app for teenagers to compliment each other, topped Apple’s App Store charts and quickly amassed millions of users among the high school demographic. Facebook Inc. acquired it less than three months after launch — and closed it soon after.

Now one of TBH’s co-creators is back with Gas, an almost identical app for iPhone. Gas asks teenagers multiple-choice questions about people at their school, allowing them to choose ratings such as “the most beautiful person you’ve ever met” or the classmate who is “never afraid to get into trouble.”

As in TBH, the questions Gas asks are positive in nature and encourage teenagers to compliment each other — that is, cheer each other on. Those who are chosen in the polls receive a “flame” – a message that they have been chosen. Voting is anonymous – people only know the gender and grade of those who voted for them. But users of the free app can make internal purchases to learn the names of their fans, or to hide their name.

According to Data.AI, users have downloaded Gas more than 500,000 times since its launch in late August.