Development software for AR applications is largely dependent on the platform. However, augmented reality programs themselves make use of computer vision to find markers that can be associated with known landmarks. Additionally, virtual reality software uses tools in your smartphone such as the compass, accelerometer, and camera to match up those data points and then render imagery on the landmarks themselves. Augmented reality software makes use of 3D imaging technology to detect features like corners, and edges, which allows for more accurate rendering. Naturally, GPS and WiFi signals can also be a huge help to AR software applications locate the right information for location based data downloads.
Some common tools and brand names of AR software include ARToolkit, ATOMIC, Mixed Reality Toolkit, OSGART (ARtoolkit and OpenSceneGraph software) and mixare for the ANDROID platform. OpenMAR for the Symbian platform which is released under the Eclipse Public License.