NFC or Near Field Communication is the technology that contactless payments with phones use where a phone can be placed near a terminal and a payment is made or when “smart cards” are used in a hotel or an office to undo locks on doors to give people access. Very useful but it’s true to say that there are more fun things we can do with NFC!
First thing we need to check is that we have an NFC enabled phone you can usually turn on or off the NFC function on a mobile phone in the settings. If you have an NFC enabled phone (Android or Apple) you can use your phone to both set up or “write to” an NFC tag and to “read” the contents of an NFC tag.
NFC tags are available in all kinds of formats and types. We used some “Mifare” tags for our experiments and these are available in all kinds of shapes and sizes from small stickers to blank credit cards, keyrings and more can all be found online. They can also increasingly be found embedded into objects like rings and necklaces. We bought some small stickers and began to play with them. To read and write to the NFC tags we used a free android application on our phone called “NFC tools”.
NFC tags are brilliant in that they don’t need any power supply to operate and they rely on the powered “active” device, in this case our phone. On the NFC chip there is a super fine coil of wire which acts as an inductor and, put simply, can induct power from the transmitting device. Apart from the cool power stuff NFC can contain a small amount of data. Whilst actual amounts vary across different tags, our tags could hold 1 kilobyte of data. A kilobyte is not a massive amount. A simple way to think of a kilobyte is it can contain a 1000 letters, or characters, including spaces! As an example this last paragraph you read is 653 characters long.
1000 letters isn’t massive but it is enough for a short message, say up to roughly 150 words. Our NFC tools app allowed us to directly type text into it and then write this text directly onto the NFC tag. Once we had done this we could then hold our phone close to the tag and our phone would automatically scan the tag and open the message in a window on our phone. So our first game was to stick a tag at a “secret location” (actually this a bench in our garden) and then our family and friends could use this to read and leave secret messages for each other to read.
We noticed that sometimes NFC tags are used on public transport to allow people to scan and be directed to a website, this gave us our second fun idea for a group of friends. We stuck an NFC tag into a toy and set the tag up using NFC tools to link to a Google document. We set up the google document so that anyone with the link can edit the document and we started the document off with the name of our toy and the idea, the idea being that we can pass the toy between our friends and each friend can update the google document with a log of the adventures that the toy gets up to! All the friends that have or have had the toy can then still keep the link and log in to the document and keep up with the adventure!
We went one step further with this idea and actually made a small toy, we had a silicone mould sold as a baking accessory that allowed us to cast small figures. We used some epoxy resin (leftover from another project) and cast a figure. Whilst the figure was still wet we used a toothpick to gently push one of our NFC stickers inside. Once the casting was fully hardened our little character was ready to go off on their adventures!
Learn More
What are NFC Tags
https://electronics.howstuffworks.com/nfc-tag.htm
What is NFC
https://www.howtogeek.com/137979/htg-explains-what-is-nfc-and-what-can-i-use-it-for/
Creative uses for NFC tags
https://trendblog.net/creative-and-useful-ways-to-use-nfc-tags-with-your-smartphone/
Let’s talk about NFC tags
https://www.cgatechnology.com/lets-talk-about-nfc-tags/
What is NFC?
NFC Tag Game
NFC Tags with books
https://www.smartrac-group.com/how-nfc-keeps-children-engaged-with-books.html
