Form Factor

Form factor refers to the overall physical size, shape, weight, and mechanical configuration of a device — for mobile phones this includes distinctions like candy-bar, clamshell (flip), slide-out keyboard, foldable, and modern all-touch slab. Form factor has direct accessibility consequences: the physical arrangement of buttons determines which users can reliably operate the device without accidental presses; the position and angle of the screen affects glare and readability for low-vision users; weight and grip surface affect usability for people with tremors, arthritis, or grip-strength limitations; and the mechanical action required to open a clamshell or slide-out case can be a barrier for users with motor impairments. Accessibility evaluations therefore need to cover the device's form factor as well as its software.