Textropilis and Fishtropolis are very similar apps. The idea is that you start out with a city or fish name, try to make as many words as possible with those letters, and earn more cities and fish to move up. The levels get progressively harder as the expectation to create more words moves higher. Another cool feature I like about these apps is that it has the definition of the words shoot across the screen as you submit them. Both apps work on the iPod and iPad. If you are looking for a good activity for students to make words, these would be good for you.