An Ontario Court of Appeals issued a ruling in a case where a school teacher was issued a laptop that he was entitled to take home to use on non-scheduled work hours. During his spare time he was looking at pornographic images which were uncovered during a police search of the computer. The Court of Appeals decision stated that if you issue a employee a laptop or a smartphone and let them take them home or on vacation, the employer has given the employee explicit permission to use the devices for personal use and thus they have the right to expect a reasonable amount of privacy.
While we recogize that Canadian law is not viable in the US, we would suggest that part of your corporate policy needs to clearly state the expectations you want from employees that you have on 24/7 status. Clearly delineate what they are able to do with those devices. If you don’t want them usig the devices for personal use say so. You decide the direction your organization goes in this social media world we are living in.