Button functionalities for user interfaces, e.g., for use with a portable multifunction device, are disclosed. Exemplary button functionalities are described for an electronic device with a display, a rotatable and depressible input mechanism, and/or a button. Different device features may be accessed, depending on whether the rotatable and depressible input mechanism or the button is activated, and further depending on whether the activation represents a single press, a double press, or an extended press on the rotatable and depressible input mechanism or the button.