@BisonHero: You could try introducing them to Risk Legacy - could easily tell them it's just "Risk 2". I haven't played it yet but I'd say it's suitable for you and your friends. Unlike other board games, Legacy evolves by encouraging you to write on the board, rip up cards, etc. so it's great for a group of friends.
There's so many excellent games on iOS you're bound to find something you enjoy. Like others have said, take a look at the App of the Day stuff over on Tested.com, and also browse TouchArcade.com where they do a pretty good job of curating some of the best apps.
Personally I like games I can pick up for 60 seconds, play, and put down again - so from the games I've been playing recently I'd suggest: