I'm a shaaaaaaaaaark! Wait no I'm not, that's Hamza. Anyway, to celebrate Shark Week on the Discovery Channel, Future Games of London has made its Hungry Shark games free for the whole week. It's basically Feeding Frenzy without the Katamari gameplay, so it can get old if you play it too much -- but you're still a shark.
You can grab Hungry Shark 1 (regular, HD), Hungry Shark 2 (regular, HD), and Hungry Shark 3 (HD) but make sure to grab the version that works with your iDevice. Part 3 is about the same as Part 1 with more fish, while Part 2 has a larger level and penguins to eat. Penguins!
There are some paid in-app purchases as well if you're into that, but they are not required to play the game nor are they really in your face about it.