Hi Adafruit community,
after been looking around the forum quite a while i couldn't find what i was looking for, so here i am asking help to the experts.
I had this idea for a project that, whenever comes in range of a "sensor", switches on (HIGH) a LED/motor/whatever other device, and keeps it that way until the, let's call it "sensor", is couple of meters away from the device above mentioned.
One of the "sensor" could be a mobile phone which is why i thought bluetooth could be a good idea, but after looking around at all the shields available i've noticed that are a bit oversized compared with what my constraints are. So here's the idea of using an RFID/NFC tag in order to activate the device, and hopefully leave it HIGH until is next to it.
I'm open to any solution as long as is compact and in an acceptable price range.
Thanks in advance