I like simple software packages and this is certainly one of the most simple I have ever used. Although the technology behind it is a little more intelligent. If you're an adventurer or even just someone who enjoys a walk then you might find Compass a good addition to your mobile, especially if you like adventuring in places you've never been before and might have difficulties getting home from.
It's very simple to use and the compass is big and clear. Just rotate the phone so that the sun and moon symbols match up with the sun or moon in the sky and you can see which way is North. However, while not a navigator myself, that all sounds too simple and with a dangerous chance of being not accurate, or not accurate enough. With GPS software on many phones now perhaps Compass is a step in the wrong direction.