Abstract: The invention relates to an alphanumeric keypad (1), especially foldable alphanumeric keypad, which is stored on the back of a mobile phone. The alphanumeric keypad (1) (membrane keys, pushbuttons and/or touchscreen display pages) is stored in such a way that it closely follows the shape of the mobile phone. When needed, this keypad is folded out (3) and functionally connected to the front keypad by means of a switching contact. Now, the message can be quickly typed in and sent. After the message has been transmitted, the keypad is folded back and the connection disabled. The touchscreen display pages can be used for interactive communication (keypad) or for displaying Internet pages.