That is correct, you can have multiple Slingboxes under the same account. You would be able to control any Slingbox in the account from one device. The links below provide more information on how to do so. Hope this helps!
- Slingbox.com - What do the buttons on the main SlingPlayer for iPhone screen do?
- Slingbox.com - Launching SlingPlayer if you have more than one Slingbox
Sling Media Moderation Team