1. A portable electronic device, comprising: a memory configured to store instructions; a screen configured to display data; a keyboard including a plurality of physical keys configured to receive key inputs, each of the physical keys being associated with inputting a primary character and a secondary character; and a processor configured to execute the instructions to: detect an input of a physical key; determine whether the input is a press input or a tap input, the press input being associated with inputting the primary character, and the tap input being associated with inputting the secondary character; and enable display on the screen of the secondary character associated with the physical key based on the determination that the input is a tap input.