0. Introduction to NFC and NTAG216

What is NFC?

NFC (Near Field Communication) is a short-range wireless communication technology that allows devices to exchange data when they are brought within a few centimeters of each other. It is commonly used for contactless payments, access control, and data sharing between smartphones and NFC tags.

Frequency Used by NTAG216

NTAG216 tags operate at a frequency of 13.56 MHz, which is the standard frequency for NFC communication worldwide. This frequency enables fast and secure data transfer over very short distances.

Safely Using NTAG216 Tags for Custom “Tap on Phone” Actions

Use trusted NFC programming apps like NFC Tools or NXP TagWriter.

Program only non-sensitive information or URLs that use HTTPS to ensure secure connections.

Avoid storing personal or confidential data on the tags.

Test the programmed tags on your own devices before sharing.

Inform users about what the tag does to avoid unexpected behavior.

By following these guidelines, you can create reliable and secure “tap on phone” experiences that provide useful information or automate simple tasks.

📘 Comprehensive How-To Guide

Program NTAG216 NFC Tags on an Android Phone (Using Free Software)

  1. Check That the Android Phone Supports NFC

Most modern Android phones do, but it’s worth confirming.

How to check:

Open Settings

Search for “NFC”

If you see a toggle for NFC, turn it ON

If NFC is missing, the phone cannot program tags.

  1. Download a Free NFC Programming App

Two excellent free apps support NTAG216:

Option A — NFC Tools (Free, Easy, Beginner-Friendly)

Available on Google Play

Supports reading, writing, copying, erasing, locking NTAG216

Very intuitive for first-time users

Option B — NXP TagWriter (Free, Made by the NTAG Manufacturer)

Also free on Google Play

Extremely reliable for NTAG203/213/215/216

Great for writing URLs, text, WiFi configs, business cards

Either app works perfectly for NTAG216.

  1. Prepare Your NTAG216 Tags

NTAG216 tags are:

NFC Forum Type 2

888 bytes usable memory

Fully writable and rewritable until locked

Make sure your tags are blank or not locked.

  1. How to Write Data to an NTAG216 Tag (Using NFC Tools)

Step-by-Step:

A. Open NFC Tools

Tap Write

Tap Add a record

B. Choose what you want to write

Examples:

Text

URL

Phone number

Email

WiFi network

Bluetooth toggle

App launch

Geolocation

C. Add your content

Type the text or paste the URL

Tap OK

D. Write to the tag

Tap Write

Hold the back of your phone against the NFC tag

Wait for the confirmation message: “Write successful”

If it fails, lift the phone and try again—alignment matters.

  1. How to Erase or Format an NTAG216 Tag

In NFC Tools:

Go to Other

Choose Erase tag or Format tag

This removes all NDEF records so you can start fresh.

  1. How to Lock an NTAG216 Tag (Optional but Permanent)

Locking prevents further edits.

In NFC Tools:

Go to Other

Tap Lock tag

Confirm

⚠️ Warning: Locking is permanent on NTAG216. You cannot unlock it later.

  1. Advanced Programming (Optional)

If you want deeper control—full memory dumps, APDU commands, UID-changing magic cards, etc.—you can use:

  1. Troubleshooting Tips

Tag won’t write?

Ensure NFC is ON

Move the tag slowly around the back of the phone

Remove thick cases or metal plates

Make sure the tag is NTAG216 (not Mifare Classic)

Tag writes but won’t trigger actions?

Some actions (like toggling Bluetooth) require the NFC Tools: Tasks companion app

URLs must start with https: Some phones restrict automation unless the screen is unlocked 9. Quick Comparison Table Feature NFC Tools NXP TagWriter MTools BLE Free ✔️ ✔️ ✔️ Beginner-friendly ⭐⭐⭐⭐⭐ ⭐⭐⭐⭐ ⭐⭐ Supports NTAG216 ✔️ ✔️ ✔️ Write text/URL ✔️ ✔️ ✔️ Automation tasks ✔️ ❌ ✔️ (advanced) Full memory dump ❌ ❌ ✔️ Best for Everyday use Business cards, WiFi, URLs Power users 10. Recommended Software for Programming NTAG216 on a Modern iPhone Modern iPhones (iPhone 7 and later) support NFC tag reading and writing with iOS 13 and above. To program NTAG216 tags on an iPhone, you can use the following apps: NFC Tools (iOS) Available on the App Store User-friendly interface similar to the Android version Supports reading, writing, erasing, and locking NTAG216 tags Allows creating custom “tap on phone” actions such as URLs, text, contacts, and more NXP TagInfo Available on the App Store Developed by NXP, the manufacturer of NTAG chips Provides detailed tag information and basic writing capabilities Shortcuts App (Built-in) Use Apple’s built-in Shortcuts app to create NFC automation Program tags to trigger custom shortcuts that can display information, open apps, or perform tasks Requires iOS 13 or later and iPhone XS or newer for writing capabilities Tips for Safe and Effective Use on iPhone Always use apps from trusted developers like NXP or well-reviewed apps like NFC Tools. Test your programmed tags on your own iPhone before sharing. Use HTTPS URLs for secure web links. Avoid storing sensitive personal data on the tags. By using these apps, you can create seamless and secure NFC experiences on your iPhone similar to Android devices. 11. Printable Mini-Guide (Shareable) 1. Turn on NFC in Settings. 2. Install “NFC Tools” from Google Play. 3. Open the app → Write → Add a record. 4. Choose Text/URL/etc. 5. Tap Write → Hold phone to tag. 6. Wait for “Write successful.” 7. Use Other → Erase/Format/Lock as needed.