The popular dating app Bumble has gone public in an initial public offering, raising $2.2B in its first day of trading this month, and a valuation of $7B as shares sold for an increasing price. As a result, Bumble founder and CEO Whitney Wolfe Herd is a billionaire, with her stake in the Austin, Tex.-based company coming out to $1.5B. Shares went public at $43, higher than the initial offering, and have gone up since. More than 50M shares have been sold so far. Wolfe Herd co-founded the dating app after helping found Tinder; she left the company and sued over sexual harassment. She went on to found Bumble, which launched in December 2014; it features a swiping-based user interface like other apps, but is designed for women to be the first to message. Wolfe Herd is the second woman to bring a company to an IPO, and at age 31, the youngest to do so. Per Bumble’s filing, more than 40M people use the app each month. The company is trading on the NASDAQ exchange as BMBL.