A display apparatus adapted for a portable device is provided. The display apparatus includes a storage unit, a primary display, a secondary display, a touch pad, and a processing unit. The primary display is in a larger size than that of the secondary display. The primary display is capable of displaying a virtual keyboard in a power off state. The touch pad is positioned on the primary display, and is capable of generating an operational signal in response to a touch operation on the virtual keyboard. The processing unit is configured for recognizing the operational signal from the touch pad and performing a corresponding control on the primary display and the secondary display. A related display method adapted for the portable device is also provided.