Flip (form)

The flip or clamshell is a mobile phone form factor feature phone which is in two or more sections that fold via a hinge. If the hinge is on a long edge the device is more likely to be called clamshell than flip phone (e.g., Nokia Communicators).

When the clamshell is open, the device is up and ready to be used. The interface components are kept inside the clamshell, which offers more surface area than when the device is closed. Interface components such as keys and display are protected when the clamshell is closed, and it is shorter or narrower, making the device easier to carry around. A disadvantage of the clamshell design is the connecting hinge, which is prone to fatigue or failure.