Lego WeDo is not the mobile. You can control your vehicles by using a computer and this is limited by the length of the USB cable. As you can see we overcame this barrier by installing on this machine tablet with Windows. Right track of the vehicle is powered all the time with battery Box, and the other via a USB hub connected to tablet. The left track movement depends on the sensor distance. When the vehicle approaches the obstacle, the left track changes the direction of rotation for 1 second that causes the rotation of the vehicle. In the second version of the vehicle rotates at random by 1,2,3 or 4 seconds.
To control, as always, we used the Scratch program.