UrbanSitter is one of several “AirBnBs for babysitting” that have dominated a traditionally cash-based, word-of-mouth market by using Facebook Connect to create the privacy and security needed to bring babysitter booking online. UrbanSitter also allows parents to pay babysitters via credit card, a huge plus for many people who don’t want to carry large amounts of cash to pay for childcare. CEO Lynn Perkins said about half of parents using the site pay their sitters online.

The company, which launched in San Francisco in September 2011, released a mobile app this September that allows parents to book and pay on the go, and has seen a dramatic increase in growth, acquiring more than 22,000 members so far and seeing 35 percent growth per month. The company takes a flat $7.50 fee for bookings, which ends up being about 15 percent of an average transaction.

Perkins said the company is excited about expanding into new physical markets, growing the number of cities where UrbanSitter operates, but also expanding into full-time and part-time nanny placements as well as last-minute babysitting. She also said they plan to add an Android app since they’re currently on iOS only.

“This gives us leeway to try new things,” she said.

The most recent funding round also saw participation from earlier investors, including First Round Capital, Rustic Canyon Partners, Menlo Ventures and several angels.

John Balen, general partner  with Canaan who’s joining the UrbanSitter board as part of the deal, said he’s excited about the company’s concept and thinks it’s come along at the perfect time in customer internet adoption.

“The idea makes sense, and we’re just enamored with what they’re doing,” he said. “It’s just a function of the average consumer is getting more comfortable with these tools.”

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