When Firemint, the creators of the popular iPhone air-traffic-control simulator Flight Control, began working on a version of the game for the iPad, the company decided to move beyond the tablet’s roomy screen and into the third dimension.

The new version is called Flight Control HD and available now in the Apple App Store includes a new airfield that looks best if you are wearing a pair of red-and-blue anaglyph 3-D glasses.

However, players eager to experience the new multidimensional airfield will have to pick-up their own set of 3-D viewing glasses, said Alexandra Peters, community manager at Firemint.

“It’s more of a quirky surprise more than a big selling feature,” she said. “They’re the low-tech glasses so they are easy to find on Amazon.”

The iPad version, which costs $4.99 to download, allows two players to do battle with one another on a split screen. Players can also play against each other using multiple devices, including iPads, iPhones and iPod Touches, over a Wi-Fi network or Bluetooth.

Firemint, which is based in Melbourne, Australia, has posted a preview video on YouTube, though it doesn’t show the 3-D airfield.

On Tuesday Yahoo introduced two new search iPhone applications at the C.T.I.A. conference in Las Vegas.

One of the apps, called Yahoo Search iPhone App, is an integrated search service for the Apple iPhone and includes a number of interesting features, including voice search and “Shake to Clear,” which does exactly what the name describes: clears the last search when you shake the phone.

The new app also offers a range of new local tools and features  that can refine a Yahoo search based on a user’s current location and also add relevant maps using location-aware technology.

The other new iPhone application is called Yahoo Sketch-a-Search.

The service works by allowing users to draw a boundary on a map around a specific location. The app will then bring up local content, including restaurants and businesses, without a user needing to know the name of an area or neighborhood. In addition, the app also filters restaurant results by cuisine, ambiance and star rating, Yahoo said.

The release of these new applications and other recent mobile content shows Yahoo’s continued efforts to stay involved in the growing mobile space.

In the early days of the Internet on cellphones, Yahoo was considered a thought leader, releasing numerous mobile applications around news, search, mail, and chat. Over the last several years, Yahoo’s competitors have quickly surpassed the company by releasing handsets, operating systems and entire ecosystems around devices.