A push-button hinge for a handheld device. The hinge comprises an axially movable button having a push surface and a helical portion for converting axial movement of the button to rotation, a helical follower engaged with the helical portion for rotating in response to the axial movement of the button, a cam rotatably movable with a flip part of the handheld device, a cam follower engaged with a cam profile of the cam and rotatably movable with the helical follower, and a biasing member for urging the cam against the cam follower. The cam profile includes an area initially resisting opening of the handheld device that is overcome by rotation of the cam follower in response to the axial movement of the button. The cam profile further includes a slope for causing rotation of the cam with respect to the cam follower due to the biasing member, thus rotating the flip part and opening the handheld device.