Shirt button cameras are the industry standard. One way of stabilizing the button camera (which is disguised as a shirt button) is to attach it to a bra, at the back of the camera. Many, like me, use a shirt mount, which allows us the adjust the camera height as necessary during a shop by just tugging gently on the shirt shoulder seams.
DO NOT buy any video camera with the idea of being paid to do video shops without checking with a major video MSC about equipment that meets the industry standard. For that purpose, no pen camera or broach camera or eyeglass camera will do.
Based in MD, near DC
Shopping from the Carolinas to New York
Have video cam; will travel
Poor customer service? Don't get mad; get video.