A handheld electronic device (200) is provided. The handheld electronic device mainly comprises a first casing (210) and a second casing (220). A display screen (212) and an image-capturing apparatus (222) are set up on the first casing and the second casing respectively. The display screen is positioned on a front surface (210a) of the first casing. The second casing is pivoted to a rear surface (210b) of the first casing and the second casing is permitted to flip between first and second positions. At the first position, the second casing is received in a recess defined in the rear surface of the first casing, and the image-capturing apparatus faces rearwards. At the second position, the second casing is located above the first casing, and the image-capturing apparatus faces forwardly.