The general look, or size and shape, of a mobile device. All mobile phones are similar at the physical style level. Most devices fall into one of the following categories: Bar, Clamshell, Flip down, Slide or Swivel. Mobile manufacturers come up with new designs, but the base they use is normally one of these form factors.
![](http://www.gizmoaxis.com/wp-content/themes/nanomag/img/feature_img/slider-feature.jpg)