Rent.com is taking a big step into the mobile world with the beta launch of its redesigned website, one that uses responsive web design to deliver an experience that's usable on desktops, laptops, smartphones, and tablets. Head of Product Amanda McConnell and Chief Technology Officer Alain Avakian gave me a preview of the redesign last week. It's very clean, with big images and text, and if you're looking at it on a smartphone, the page elements that won't fit on the narrower screen just slide down, forming a more column-style layout. The site previously released native iOS and Android apps, but the focus for the past few months has been on the redesign. With this approach, when Rent.com rolls out new features, it can immediately push those changes to its visitors on all devices. Plus, a lot of Rent.com's traffic comes from search, and it's better to give mobile visitors who arrive that way a mobile-optimized web experience, rather than forcing them to download an app. Mobile traffic now accounts for 25 to 30 percent of Rent.com's traffic, Avakian said, and he expects it to go as high as 40 percent in the next few years. At the same time, McConnell said that with 3 million unique monthly visitors, the site can't be quite as experimental as a startup: "We have to be a little bit more startegic how we're going to be making changes." So the new design is only available to select users for now, with plans to make it fully available by the end of the first quarter of 2013. Other changes in the redesign include the ability to search for listings nearby, a new grid view and map view for browsing search results, and the ability for renters to track their activity on the site, so they can save their favorite properties for viewing later. And while this isn't directly related to the redesign, Avakian also pointed out that Rent.com has a different business model than most apartment listing sites: it only gets paid when the property owner actually finds a renter, so "we optimize our site for driving renters to find that right apartment." Rent.com says it worked with Filament Group to create the new design. You can sign up for the beta here.