"We are much more like a mobile, optimized, well-lit Craigslist than anything else," co-founder and CEO Bo Fishback said.

So will the location-based apps change the mobile landscape or are they a flash in the pan? One factor that has the potential to slow growth is user concern over privacy protections.

Location data has opened up a flood of innovation, but has also among privacy advocates and privacy-sensitive users.

The new class of apps obtain location data in a variety of ways. Highlight, which launched at SXSW, gets GPS data directly from the user's mobile phone. TaskRabbit and Zaarly use GPS data from phones, but can also run in a desktop browser. Other location-based apps build on location data gleaned from user-submitted content on social networks including FourSquare, Facebook and Twitter.

Annette Zimmermann, an analyst at Gartner, said that privacy is an issue in most of the location-based apps, which, she said, "do not have the transparency that one should wish for consumers, so that they understand clearly when they share their location and with whom."