For SlingPlayer to work, you must have A PC or MAC with SlingPlayer installed for setting up internet viewing on your Slingbox with a broadband upstream connection of at least 256K. Click on the source link to see the minimum and optimal OS required for each supported BlackBerry device. The app has a one time charge of $29.99 and there is a 30 day free trial, and can be downloaded at mobile.slingplayer.com.
Furthermore, Sling Media has submitted an iPhone version of the SlingPlayer Mobile to the iPhone App Store. You can sign up for an alert so you can be notified when the app will be available for downloading.
source: Sling Media (BlackBerry), (iPhone) via EngadgetMobile