Guys, I have some sympathy with Trevor here, I have never seen the Radar screen on my setup either, but just assumed it was only available on IOS, and I use Android exclusively, on both my HTC One phone, and Huawei 8" tablet.
Peter, until I get back to my aircraft (my PAW is behind the panel) I can't repeat your suggestions, but I use the options you say and have never seen the small radar display on my main SD screen. Graham, I tried your Simulation exercise, and couldn't see the Radar display (however, I'm not sure how to "spawn" traffic).