Like real estate, mobile is about location, location, location. That means that direction is an important item. And just as important is how this information is presented to the user. In Nov. 2011, we talked about building a user interface in Mono For Android. In this article, I'll expand a little bit on that by creating a compass that displays north. We'll use Android's built-in sensor support to determine the orientation of the device, then use a custom control to display North. The output will look like