If you’re planning to stock smart jewelry, consider these key issues of form and function:1. Will the piece compete with a watch? If you’re considering a bold bracelet, ask yourself if customers will give up their watches, or wear both together.2. Will it be too heavy? A piece that looks great in the case could literally weigh down customers. 3. Are there customization options? Some smart jewelry devices let the user switch out settings, bands, and other features to coordinate with multiple looks.4. Can it get wet? This is especially important for fitness and activity trackers, which