This game is a scrabble clone that can be played at your own pace, meaning you can play it during breaks at work or (I do not condone this) at long stop lights. It was originally for iOS, but has recently been released for Android. You can play with people on your contact list, or find random games online. It's very addicting, and is a very good time killer.
If you do play it, post your screen name here. Mine is "icekitsune".