Another addictive free game for you readers. I present: Ninjump!
Personally I like this one even better than angry birds. It's very easy to play but can be pretty challenging to master. You play as a ninja running up a wall, you tap the screen to jump-attack to the other wall. As you go along you'll be attacked by birds, squirrels and other ninjas, and you have to jump back and forth to dodge or kill them and avoid obstacles. If you kill three of the same type of enemy in a row you get a temporary boost by taking on the form of whatever you killed and get to go really fast and be invincible for a short time.
This is one of my favorite games for my phone right now because it's fun, fast paced, easy to play, and I usually die and start over pretty quickly so it's a good game to play while waiting in line or whenever you just want something to kill a little bit of time. Short games make it easier to put it away if I have to (since I don't like quitting in the middle of something). It is pretty addictive though and I could play it for long periods easily.
This is my personal high score at the moment, and I challenge any of you to beat it. Let me know if you do. :)
Here's the QR code for it, so get jumping: