As smartphones continue their unimpeded march into the pockets of millions of worker bees, new modes and patterns of user behavior--good and bad--are evolving constantly. (Take ringtone download trends as a quick example.) BYOD or no BYOD, what people do with those phones all day (and night) can cross all kinds of lines with compliance, laws and regulations, company policies, and most frequently (and alarmingly), basic common sense. Those smartphones might be smart, but the user behavior can get pretty dumb--not to mention costly and risky for employers.

So how does a company establish a few iron-clad rules of mobile behavior? First, recognize that your mobile policy (you do have one, right?), and the ethical guidelines that follow, need to mirror the practices and policies that govern your company generally. Second, commit to educating and communicating with your employees about what defines a good mobile code of ethics.

Here are a few principles to start with:

1. First and Foremost: Do Your Job

Zero tolerance for texting, personal calls, and cameras made sense in the early days of mobility, but no more. Mobile infuses our personal and professional lives too much for outright bans to be practical. But the importance of productivity means that companies should not be laissez-faire about mobile use at the office, either. Instead, find a middle ground: Make sure your employees separate personal from work-related mobile communications and that they understand that, worked-related or not, these devices should never distract them from communicating in the workplace.

2. Protect Confidential Info

The increased presence and usefulness of mobile devices for work purposes means that we can take our jobs with us almost everywhere. It also means that we can possess sensitive and confidential emails, documents, and conversations that, if lost or mishandled, can land companies in a heap of trouble. Set up systems that allow your employees to protect the information on their phones (from security apps to encrypted documents), and be clear about the importance of doing so.

3. Show a Little R-E-S-P-E-C-T

If your company purchases mobile devices for employees (or reimburses them for using their own) make it clear to your workers that that they have to hold up their end of the bargain, too. Company devices need to be treated with respect, and while the occasional loss, theft, or shattered screen is inevitable, enlist all of your employees in the proper care of company-related equipment. Put it to them in layman's terms: "If you just bought an iPhone 5, would you want to leave it at the bar after Friday happy hour?"

4. Know--and Follow--the Law

Mobile devices in the workplace mean that your company can find itself liable for the bad, or even just careless, behavior of your employees. Depending on the time, place, and involved parties, sexting can constitute sexual harassment. Employees texting while driving a company vehicle will become your problem too. Read up on the legal pitfalls of mobile devices in the workplace, and make sure your employees understand them too.

5. Respect Others' Privacy

When it comes to smartphones, it's important to maintain a level of trust between yourself and your employees. No, they shouldn't have free rein to do as they please on a company phone. But, they should also feel comfortable calling home to check in on the kids, browse Facebook during lunch, or respond to a text between meetings. Ideally, all personal interactions will happen outside of work, but make it known that if they respect your mobile policies and the company's time, you'll respect their need for privacy.

6. Get a Refresher on Common Courtesy

Mom said it best: Play nice. Mobility has changed how we work and live, but common courtesy--and some common sense--go a long way. You wouldn't like it if a  job candidate checked his phone during an interview, would you? Show him the same respect. Oh, and you don't have license to text an employee after hours--unless it's critical for work and she's given you explicit permission to contact her that way.

While "Don't be stupid" is no way to frame an ethical policy, emphasizing common sense and good behavior is fundamental to any effective mobile code of ethics.