Anthemos Georgiades says he grew up in a real estate family in London, so it’s quite natural that his startup, Zumper, is initially geared to helping landlords and brokers do business on the go.

Zumper’s iOS app for real estate professionals, which launched just a little over a month ago, now carries hundreds of new listings each week in San Francisco, Chicago and New York. It is slated to go national in July.

Also next month, the SF-based startup will release an iOS app for renters, with the focus being on neighborhood search.

Zumper takes particular care to make sure its listings are up-to-date and accurate. “We get all of the listings ourselves as data feeds from large brokerages or from landlords themselves,” Georgiades says.

The service is free.

Those seeking a place to rent start out with a city map and then can quickly zero in on neighborhoods. They can set up a listing feed that will alert them when a new rental comes on the market within the parameters of price, size, location, etc., they have set.

Georgiades says he notices a difference in how renters use Zumper in San Francisco as opposed to New York:

“San Francisco renters are very tech savvy. They create more listing feeds than New York users do. They embrace the new way of doing things faster. They will create more messages to landlords than a New Yorker will create.”

The core users of Zumper are young professionals or recent grads starting out at work after college. They are the kind of prospects who go to open houses with their credit reports and other documents in tow.

The company is developing online tools to help them with this process of competing for rentals.

On the landlord side, Georgiades says most users choose a mix of the mobile and web solutions offered by Zumper.

“It is a surprise that while they think the mobile product is great, they still like the web version as well. In fact we get more web usage now that we have mobile. The majority use their iPhone to take photos of the unit, and enter the basic data to create the listing but wait until back to their office to finish it. The mobile and web apps sync so that is not a problem.”

The company has a team of seven, six here and one in Manhattan. The company originally launched on the web at TechCrunch Disrupt last September.

The name Zumper is a play on a British real estate term gazump. “It has a somewhat negative connotation having to do with a last-second deal, but we wanted to add a positive twist in that our data is real-time and accurate. So if an apartment comes on the market, it’s on our site; the minute it goes off the market, it’s off our site. Zumper.”