This is a very good question. With the iPad we were seeing an issue with the App crashing when trying to connect to the Slingbox. We have since released a update that should have corrected that issue. The new App version is 3.1 please make sure that is what you are running on your iPad.
Hope this helps,
Sling Moderation Team
I just installed this app on my ipad 2. I read that it worked with a HD PRO Slingbox but I missed a small asterisk at the end. Down below it explains that the app doesn't work with the HD PRO. It is very confusing the way it is listed. I hope they fix the problem or give my money back. I also have the iPhone app and it works fine.