Issued NEXTEL. It is mandatory to keep it "on or about your person" when on-duty. I used to leave it in the call, but as a supervisor, I have to always have it, because dispatch or the troops are always "bumping" you. Set on vibrate it causes no stealth issues, and makes for a great back-up commo device and way to keep more sensitive comms off the regularly scanned airwaves and off recorded channels.
As to the personal end, it used to be pretty open-ended, and you use it for personal business as long as you didn't burn too many minutes per month. They just changed it to pretty much eliminate all but brief personal calls.
What is bad about them is they eliminated pagers for us on-call folks and are using paging over NEXTEL, which means that anyone who has your cell phone number can and will call you whenever they feel a compelling need, and the phone is sitting on the nightstand so I don't miss a call-out. This may get a litttle ugly when we go to nights.