There are a few apps on the Play Store that will allow you to control your MAC from your Android. There are plenty of reasons you would want to be able to control your Mac with a smaller Android device. If you are giving a presentation you may have your Mac connected to a projector and need a remote to control it while across the room. With mac.remote you are able to control iTunes, Spotify, Rdio, MPlayerX, VLC, Keynote, and iPhoto. You will be able to Play, Pause, display current track info, go to previous, go to next, rewind and fastforward. The media keys in .remote will control the mac media keys including long press. You will also be able to shutdown, suspend, and adjust brightness and volume. For more information on this app head to the link below.
Play Store