Clash of Clans is a brilliant “RTS/Time Management” style game. Clash of Clans is a universal iOS application that will run on your iPad, iPhone, and iPod Touch. It is a free download in the App Store but relies heavily on In-App Purchases. IAP are not required but honestly to enjoy the game you will need to purchase gem packs in order to find the game enjoyable or it will take you forever to build your kingdom.
I first learned about Clash of Clans by watching some videos posted on YouTube by Simon Tay. Simon also has some terrific CoC tutorials for offensive and defensive strategies, I highly recommend you check out those videos before diving into CoC.
Overall the gameplay is fantastic, I love these types of games and I used to play an online Flash based game called Evony, Clash of Clans is the first game that comes close to the fun that Evony offered. If you enjoy these types of games I highly recommend you check it out and the fact that it is free to download means it cost you nothing but a few moments of your time.
You can download Clash of Clans free in the App Store: