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What is NFC?
NFC stands for Near Field Communication.  It’s a variant of RFID (the same technology that’s used for door access in offices and in Oyster cards).  It’s how contactless payment works.


That doesn’t help me, what is it?
It’s a means of transmitting information.  Because of how it works, the information transmitted is small, usually up to 4KB.  A microchip and a coil of wire is placed inside a ‘tag’.  A reader (or reader/writer) reads the information on the tag and performs actions based on the information received.  For example, Samsung have fitted NFC readers in the back of mobile phones.  The phone is placed near enough to the tag to read it.  If the tag contains a web address, the phone will automatically go to that web site.  If it contains WiFi settings, those settings are entered in to the phone and it will connect to the router without having to put in the WiFi code.

An example of an NFC Tag

This NFC Tag will allow you access to my WiFi.


How does it work?
Data is beamed via an electromagnetic (EM) field.
We all know that electricity will power an electric motor.  You put voltage in, you get movement out.  But, if you put movement in to a motor you’ll get voltage out.
By swapping the motor for a coil of metal (copper in this instance), you put voltage in, you get an EM field out.  Flip that around and if you put an EM field in you get voltage out.
The NFC reader puts voltage in through the copper coil to generate en EM field.  If you place it near a tag it turns the EM field in to a tiny voltage, powers up the microchip in the tag then transmits it using its copper coil as an aerial back to the reader.  The reader picks up the tag’s information and acts on it.  The tag doesn’t necessarily need a battery because it only needs to power up when there’s a reader there and it gets its power from the reader.


What can it do for me?
Pretty much anything you want it to.  Tags can be programmed by your phone/tablet (you’ll need NFC to do it of course) to turn on/off WiFi, sync, GPS, 3G, adjust the volume, run Tasker profiles etc.  If you have a contactless card from your bank, or have certain apps installed (Google Wallet, Orange Quick Tap) you can pay for goods or services by tapping your card or phone/tablet instead of using Chip & Pin*.
I have an NFC tag on my keyring, the tag contains an address, it will navigate you there, load Google Street View so you know what the area looks like and text me that the keys have been found.  I have another tag on my wrist, it contains my name, NHS number and Medical Records Number so if a hospital scans it, they know who I am and what medication I’m taking.  A tag by my bedside will turn off WiFi, auto sync, GPS, Bluetooth, change the volume, and dim the screen.  When I tap it again it turns up the volume, brightens the screen, turns on WiFi etc.


Which apps can I use?
There are a few apps on the market.  I tend to use NFC Task Launcher (now called Trigger) as it ties in nicely with Tasker, thus extending what the tag can do. I’d recommend getting a few tags and having a play.


Where can I get tags from?
Take a look online.  I got mine from – a reliable supplier with excellent customer service.


I still don’t understand how it works
Magic.  It works by magic. 😉


*Rumours say NFC will become so popular that it will replace, either in part or in full, Chip & PIN in around five years.