NFC (near field communication) is a wireless technology which allows for the transfer of data such as text or numbers between two NFC enabled devices. NFC tags, for example, stickers or wristbands, contain small microchips with little aerials which can store a small amount of information for transfer to another NFC device, such as a mobile device. Current NFC tag technology relies on external power sources to enable tag activity and does not provide for self-powered or rechargeable tags.