When I was a kid this was one of my favorite books, I can't tell you how many times I've heard this story. So when the app came out I thought I'd check it out and show it to my four year old. The app works pretty well expect it is a little laggy when it starts and it has to load between every page. I'm using an original iPad, so that might be part of the problem. Neither of these problem however are that big of a deal.
The app is just like the book expect instead of having to try to read it in your best Grover voice, Grover reads it. The animations are nice and there are even parts that are interactive. The app is very nicely done and if you have a little is well worth it.
$3.99 in iTunes Store