A finger sensor apparatus may include an integrated circuit substrate for receiving a user's finger adjacent thereto, and a plurality of infrared sensing pixels on the integrated circuit substrate. The infrared sensing pixels are for sensing infrared radiation naturally emitted from subdermal features when the user's finger is positioned adjacent the integrated circuit substrate. The finger sensor apparatus may also include a processor connected to the infrared sensing pixels for generating infrared biometric data based upon infrared radiation naturally emitted from the subdermal features of the user's finger.