Have you ever tried adhesive Near-Field Communication (NFC) tags?

We tried the AD Bullseye NFC NTAG213 from Avery Dennison Smartrac. You can find the product data sheet here.

My friend purchased them in Akihabara this week. The lowest purchase quantity with the vendor in Akihabara was about 30 tags and they cost around JPY 3,000.

This is the data reported by NFC tools:

• Tag type: ISO 14443-3A, NXP NTAG216
• Technologies available: Type A
• ATQA code: 0x0044
• SAK byte: 0x00
• Data format: NFC Forum Type 2
• Size: 868 Bytes

Here is an explanation for these entries:

• The NXP in NXP NTAG216 identifies the semiconductor maker, NXP Semiconductors N.V.
• Type A is a specific kind of ISO/IEC 14443 card. See here for more.
• ATQA stands for: answer to request code A. Learn more here
• SAK stands for: Select Acknowledge
• NFC Forum Type 2 is a specific kind of NFC forum NDEF format. NFC Forum won’t give you the specs without paying, though

Records that can go on the tag

You can use the NFC tools app to write, among others, the following data:

• Web address
• Wi-Fi data
• Contact information

The NFC tools app is available on these platforms:

• Android
• iOS
• PC (Mac/Windows/Linux)

Reading reliability

My friend and I tried out reading and writing NFC tags with 3 different Apple iPhone smart phones. The NFC tag contained a single web address record. The goal was to test whether our phones would reliably pick the web address in the NFC tag up or not. These are the phones that we tried:

• Phone A: iPhone 13 Mini with iOS 18.0.1
• Phone B: iPhone 12 with iOS 16
• Phone C: iPhone 14 Pro Max with iOS 18.2.1

It wasn’t a reliable experience. Phone A wasn’t reading in the NFC correctly:

• Phone A read the web address 50% of the time
• Phone B read the web address almost 100% of the time
• Phone C iPhone read the web address almost 100% of the time

Wi-Fi records

Another surprise was the small number of NFC records that iOS accepts from NFC tags and shows to the user. Among those was the Wi-Fi record, documented by the NFC forum here, if you want to pay them a nominal fee.

iOS doesn’t support reading Wi-Fi data. See this help page here from NFC tools. It’s a safe assumption that Apple doesn’t want their phones to read this record for privacy or to reduce the vulnerability surface of their phones.

Web near field communication

Safari on iOS doesn’t support the Web NFC browser API for privacy reasons. See Apple’s response to the draft here.

Right now, only Chrome supports WebNFC. See more on this on caniuse.net.

See what Mozilla has to say about the draft here and and on their bug tracker