Form Factor


Designates the design form of the mobile device. Different designs offer different strengths and weaknesses in form and function. Listed below are the list of most common designs for basic phones:

Clamshell - Also known as a fold or flip phone, the Clamshell is one of the most popular designs, folding in half to minimize the size of the device while opening up to offer maximum screen area and keypad layout space when unfolded. A drawback among the Clamshell is the hidden internal screen when folded, prompting manufacturers to place a second external screen on the outer lid.

Block - Also known as a Candy Bar design, the Block phone offers a clean simple exterior with sturdy construction. While the lack of moving parts makes the Block phone less susceptible to wear and tear, the disadvantage is the constant trade off between offering a small device size and having a large screen and keypad for usability. The advantage is quick use without having to open or close the device, and a screen that is viewable at all times.

Slide - Similar to the clamshell but the rather than unfolding, the Slide opens up by moving two halves along a rail either assisted or unassisted by a spring-loaded mechanism. Originally conceived as a variant of the Clamshell, the Slide offers much of the same advantages of smaller size without decreasing usability, but adds the benefit of having a screen viewable in closed or open format.

Sideways - Rather than opening vertically along the hinge as the Clamshell, the Sideways design opens along a horizontal hinge. Used in many messaging-focused devices, the Sideways orientation allows for a more natural typing layout for QWERTY keyboards.