What the employer does not collect on your devices.

Basically here is what they cannot collect (it's not even an option)

Browsing history
Call history
Text messages
Other files

Additionally, the employer does not collect:

Call/SMS/Data usage
Personal applications (what you have installed)

Everything on your phone is auditable.  If anyone were to make any changes to your privacy settings remotely, three things would happen: 1) You would notice because your phone would start collecting data.  2) It would log who did it.  3) Privacy settings can only be changed on a global level, so an admin can’t target a single user to get information, HITS would have to turn it on for everyone.