Monster Feed is a colorful little tower defense title for the iPad, and it's a little more action-based than most TD titles. A lot of your interaction with the oncoming hordes is actually interactive, as you have not only towers to build and grow but also spells and even summonable minions fighting with you and at your side. Monsters have a few new tricks, too -- rather than just blindly following the paths, some will require you to tap on them or otherwise keep them back as you play. There are a few good ideas in the mix, and especially if you're a fan of the growing tower defense genre, this one seems like a must-see.
The iPad app is on sale right now for US $1.99, which is 50 percent off of the usual price. If you don't want to jump right in, you can try a lite version for free. And while the app isn't on the iPhone yet, we're told that it will be soon. If you want to try tower defense with a little bit more actual interaction, give Monster Feed a look.