It seems that you are having some issues with the SlingPlayer Mobile application for the iPhone, since you cannot get rid of the Home Channel.
You need to launch the Mobile application for the iPhone. Then log into your Sling Account. Go to "Settings" and scroll down until the "Home Channel" tab. Access this tab. On the main screen you should see the channel number (3). Delete it with the "x" located on the right hand side on the same screen and hit enter. Press the "Return" button.
Once you have applied this modification, access the Settings option on the SlingPlayer main screen and the "Home Channel" tab should be on "Not set". Log out from the Sling Account, log back in and verify that this setting is already modified. Let us know how it works for you.