Living in a castle is great but it does have its downsides. One of the main ones being that you're prone to attacks by invaders who want to get into your castle, as you'll witness in Defender.
An interesting mobile strategy game, Defender charges you with the task of defending your citadel from waves of attacks by nasty monsters. In order to block their path you need to build towers strategically in the land in front of your castle. Bricks don't come for free though, so you'll need to think carefully about where you put them and which kind of towers to use in order to maximize your defense system.
It doesn't take long to get used to the way Defender works, thanks to an interactive tutorial at the start, which walks you through the process at a gentle pace. The control system in Defender is straightforward enough and just involves clicking on the square you want to build your defense, before selecting a tower from the menu that pops up.
Overall, the game is well packaged with intricate graphics and an awesome soundtrack. The only criticism I would level at Defender is that the pop-up, tower-selection menus are incredibly small and so it's sometimes difficult to work out what you're doing.
Rather like a computerized version of Crossbows and Catapults, Defender provides an immensely fun challenge for Windows Mobile users.