If so, can I turn them on and off using an RFID reader, or possibly GPS and a mobile app?
Farsens makes a battery-free ultrahigh-frequency (UHF) RFID tag with an LED light for picking purposes. The LED does not stay on, but rather lights up when an interrogator reads the tag. You can view a video about the tag here. This is the only tag of which I am aware that contains an LED light. If any of our readers know of any others, they are invited to post information below.
—Mark Roberti, Founder and Editor, RFID Journal
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