What are the best NFC hacks

Make ingenious NFC tags yourself - this is how it works

Arne Arnold, Roland Freist

Control your smartphone individually with your own NFC tags. With these tips it's very easy - without any programming knowledge.

EnlargeHow to create NFC tags yourself
© istockphoto.com/cheyennezj

Many of the new smartphones already have them: the cool, new NFC technology. You can find it in the HTC One X, Samsung Galaxy S3, Galaxy Nexus and also in the new Windows Phones from Nokia. NFC stands for Near Field Communication. This technology transmits data over a distance of up to four centimeters. It is used, for example, to pay small amounts with an NFC credit card or mobile phone.

For the transmission there is the cell phone on one side and a "tag" on the other. This is the name of the passive RFID chip on which the data is stored, which can be read out with a smartphone. The tag is so flat and small that it can easily be hidden behind a smiley sticker or comes along as a key ring about the size of a euro coin.

How to read data from an NFC tag
To read the content of a tag, install a free app on an NFC-enabled smartphone, e.g. NFC Taginfo is recommended. Now hold the tag against the back of the phone. The app recognizes it automatically and shows the data of the tag as well as the saved content. Incidentally, the data on the tags of the new ID cards and passports are encrypted and cannot be determined in this way, NFC Taginfo can only provide information about the hardware.

What many smartphone users do not know, however, is that the NFC chips in the cell phone are also suitable for writing a tag. The apps required for this are free of charge, the tags are available for little money in the form of stickers, key fobs or chip cards in the mail order business, for example at Amazon under the keyword "NFC tags". The storage capacity of the tags is usually between 168 and 2048 bytes, depending on the design.

Pay for free with Near Field Communication (NFC)

Control your smartphone using NFC tags
Tags are particularly interesting for controlling your own smartphone. To do this, in the first step you have to provide an empty tag with the command. For example, you can program a sticker tag with the command to switch off the WLAN module. Then glue it to the dashboard of your car. All you have to do now is place the phone on it and the command will be executed: The WLAN is off and you save battery power. The apps for programming the tags offer numerous other control commands and can also move the smartphone to control specific web addresses. You can also store several commands on the tags, which are then all executed together.

EnlargeThe NFC task launcher is currently the best program for writing tags.

This is how it works with the NFC task launcher: Download the free NFC Task Launcher app to your smartphone and start it. On the first page you will find some of the program's most popular commands. First, however, tap on the plus sign in the title bar at the top and go to "New task" in the window that opens. Enter any name for “Tag Name” or accept the defaults from the program and tap on “Add Actions”. You can now choose from ten different categories. For example, go to “WLAN & Networks”, select “Wi-Fi Connection” and then tap “Next”. In the following window, enter the SSID, i.e. the name of your WLAN, select the encryption method used and enter the password or key code. Confirm with OK". You can now see in the orange bar how much storage space the command requires on the tag.

Payment by NFC - Convenient, but also secure?

Below is the name of the command with the specification of how much memory it needs on its own, i.e. without the overhead of the command language. A tap on “Save & Write” causes the “Completed” window to appear. Below you can choose between three options. “Include tag name” is activated by default, leave it as it is. Check “Write multiple tags” if you want to transfer the same command to multiple NFC tags. "Activate write protection for tag" prevents the content of the tag from being changed again after it has been written. Put the phone on a blank day. You will hear an acoustic signal and the message "Tag successfully created" appears. After confirming with "OK", the process is complete.

As soon as you put any phone with NFC support on the day, it will be recognized automatically and the smartphone will carry out the commands it contains. In our example, it logs into the WLAN. This is useful, for example, if you have a visitor who you want to give access to your Internet access with their own smartphone. The visitor then only needs to place the device on the tag. Since NFC is a standard, the commands can be understood by any phone.