Home Automation: NFC And LED Lights

Why and What:

I  bought the LIFX LED Smart Light Bulb some time back. It is a really nice LED bulb which connects to your home WiFi network. Using an app on your smartphone ( Android or iOS ), you can control the light – switch ON/OFF, change the color and intensity, invoke some special effects like – equalizer, alarm, strobe, random etc. Totally liking the bulb. Thanks LIFX!

But, I still needed to open the app and trigger the above – Not exactly equivalent to just flicking the panel switch ON or OFF.  Then came the idea of automatically switching it ON/OFF when certain conditions are met. Also, I do not want any person to operate and be able to control the lights – security matters. I can authorize only a few NFC tags with unique ID to allow the LED bulb operation.


NFC came to the rescue. NFC or Near Field Communication is a technology which is based on secure data exchange between two devices. It is hugely popular off late. NFC capable tags ( similar to RFID tags) are available easily and commonly. NFC Tags these days are not all that expensive. You get 5 re-writable NFC tags for about ₹250.00 and it can be easily sourced from ebay, flipkart etc. I used the Topaz 512, a 512 byte capacity NFC tag for my purpose.  This is compatible with many smartphones and specifically tested and found to be both writable/readable from my Android based Samsung Note 3 (SM-N9005) and my wife’s  Samsung Galaxy S5.

Google Play store has tons of NFC Apps which can read/write the tags with the information you want. I used NFC Writer by Tagstand, having found to be the simplest of them all.

LIFX community developers has developed a LIFX Plugin for Tasker which can control the lights from the Tasker App. Tasker is one of the best automation app available on android today. I regularly use Tasker to automate a lot of things on my smartphone. Now I just needed to tie the NFC Tag with certain information in it to control the LED Lights to Tasker App by creating a Tasker Task.  With that done pretty easily by the above app and the Tasker App Task to switch ON/OFF the LIFX LED Bulb, it was all ready.

One small glitch in this solution. Tasker ( as of writing this blog) doesn’t support the NFC reading for some reason. This made me hunt for the plugins for Tasker, but to no avail. After lot of searching and researching on the web, one android app called Trigger came to the rescue. Ideally I would have liked to eliminate the need for this “wrapper” app to get things done. But I had no choice. Trigger is an app in which you can create trigger tasks/jobs/apps if certain criteria is met. For example, if it is 3:00pm, turn on the radio, put the phone to silent etc. One of the trigger scenarios is the NFC Tag Read. When a pre-programmed NFC tag ( has a unique id)  is read and authenticated,   I can use this as a trigger to launch an app/task/job. This app also has the option of invoking the Tasker Task and I made use of this for my application. See diagram for more details.

Now I really need to just bring my Note3 near the NFC Tag that I have programmed earlier to switch ON/OFF the LED Bulb in my living room. I can stick the NFC Tag on my coffee table, near or on the main door, have it in my wallet or anywhere it is most comfortable to have. I have been using it for the past couple of months and working like a charm.

Block Diagram:





Tasker Setup [ Lifx ON / Lifx OFF]:

Tasker LIFX Setup

Tasker LIFX Setup

Trigger Setup:

Trigger NFC Task

Trigger NFC Task

Lifx Tasker Plugin:

LIFX Tasker Plugin

LIFX Tasker Plugin


Topaz 512 NFC tag:

Click on the image to enlarge. You will find a tiny black dot – the NFC Chip, and a coil  – used as antenna or induction coil to induce a current to power the IC Chip. Passive NFC tags work on the principle of induction to inject and power the tiny IC Chip and exchange data to and from the chip.

This particular NFC tag is a little bigger than usual. It’s sensitivity being higher due to the bigger and larger induction coil. But there are much smaller ones available as easily.


Topaz 512 NFC Tag

Topaz 512 NFC Tag

Topaz 512 NFCTag - Compared with a ₹2.0 coin.

Topaz 512 NFCTag – Compared with a ₹2.0 coin.


Apps / Tools used:

Click  below to open the App/Tool website.

Tasker App

Trigger App

Tagstand NFC Writer

LIFX Tasker Plugin

Hardware devices used:

Samsung Note 3 (SM-N9005) Android Smartphone ( NFC Enabled).

LIFX Smart LED Bulb

Topaz 512 NFC Tag