Form factor (mobile phones)

The form factor of a mobile phone is its size, shape, and style, as well as the layout and position of its major components. There are three major form factors – bar phones, flip phones, and sliders – as well as sub-categories of these forms and some atypical forms.

A bar (also known as a slab, block, candybar) phone takes the shape of a cuboid, usually with rounded corners and/or edges. The name is derived from the rough resemblance to a chocolate bar in size and shape. This form factor is widely used by a variety of manufacturers, such as Nokia and Sony Ericsson. Bar type mobile phones commonly have the screen and keypad on a single face. The Samsung SPH-M620 has a unique bar style, offering different devices on either side of the bar: a phone on one side, and a digital audio player on the other. Sony Ericsson also had a well-known 'MarsBar' phone model CM-H333.

"Brick" is a slang term almost always used to refer to large, outdated bar-type phones, typically early mobile phones with large batteries and electronics. However, "brick" has more recently been applied to older phone models in general, including non-bar form factors (flip, slider, swivel, etc.), and even early touchscreen phones as well, due to their size and relative lack of functionality to newer models. Such early mobile phones, such as the Motorola DynaTAC, have been displaced by newer smaller models which offer greater portability thanks to smaller antennas and slimmer battery packs.

A slate or touchscreen phone is a subset of the bar form that, like a tablet computer, has few physical buttons, instead relying upon a touchscreen and an onscreen QWERTY keyboard. The first commercially available touchscreen phone was the IBM Simon Personal Communicator, released in 1994. The iPhone released in 2007 is largely responsible for the influence and achievement of this design as it is currently conceived.

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