I think it's too basic for that price. It's fun but I think only hardcore Oddworld fans would bother with it. Maybe if they add in some more features such as more lines for Abe or maybe even more characters then it would be worth it.
On the other hand, the money goes to JAW and every little helps supporting the company. Just think as it as a donation to Just Add Water but your getting a free Abe Gamespeak app
