Accessories such a coat, purse, or shoes can either complete or dress up an outfit. Cell phones have almost as many accessories as Barbie does. Accessories can be practical, ornamental, or just available. In the cell phone world there are practical accessories that help you to operate the phone safely and those that allow you to carry it safely.
Some, like downloadable ring tones, are there for you if you want them. I have put accessories into groups to make them easier to describe. There are operational accessories that include battery chargers. Chargers are phone and model specific so that they are not interchangeable.
