From CNET Asia, some do’s and do not do’s on using cameraphones in public. Most of them are pretty obvious, and apply to regular photography as well, but there are few good tips, like:
DO point the lens away from others when you’re using the phone, preferably at the ground.
DO make sure you have the subject’s knowledge before mass-mailing his picture. Consent for a shot isn’t equivalent to permission for publishing it.
DON’T send photo messages to all your friends, unless you know it will appeal to them. As much as you’re proud of them, not everyone wants to see your mundane pictures. Remember, recipients often have to pay to download MMS messages.