Before I get into this, I see some potential here. This game looks like it is going to be excellent for children to play and almost every single child I see has an iPod Touch. I see several with iPhones even.
There are a few things that I can see some people getting confused with.
On the log in screen, I find it somewhat frustrating that I have to close my keyboard after typing my username and then having to close it again to press the log in button. This could be fixed if the two text bars were placed above the keyboard.
On the game itself, similar issue. I cannot read what is going on when I am typing something. I think that there should be a history bar you can open that will display the current things being said. Also, if the toolbar was above the game instead of below, it would be easier for iOS devices because the lower end of the screen is typically half taken up by the on screen keyboard.