I participated in one of the trials for Lahiru's project. The system was very intuitive: it's basically a metal detector that interacts with a computer to store state. As you approach the edge of metallic object and the metal detector beeps you can click a button to store the current location of the detector. By moving the detector along the edge of the object and storing more points you can map out the shape of the object to determine whether it is a mine or just debris.
It's nice to see this solution is getting close to shipping. Definitely a smartphone app whose value we can all appreciate.