NFC Writer: Secure Tag Setup
Read, write & verify NFC tags
Only for iPhone
Free
iPhone
Set up secure NFC tags without a subscription. Your first tag is free, then one payment unlocks it for good. No ads, no account, no server.
Write NFC tags the way you actually need to — and set up secure tags that prove themselves, without paying a monthly fee.
EVERYDAY NFC WRITING
Write text, links, phone numbers, messages, email, locations, contacts, Wi-Fi networks, and App Store links. Read any NDEF tag and see exactly what's on it.
SECURE TAGS THAT PROVE THEMSELVES (SUN)
Most NFC apps stop at plain reading and writing. This one sets up SUN.
A SUN tag computes a fresh signature inside the chip every time it's read, and writes it into the URL. The signing key never leaves the chip, so a copied tag can't produce a valid signature. A read counter goes up on every tap, so an old captured URL can't be replayed.
That's the difference between a tag anyone can clone and a tag that proves it's the original.
WHAT YOU CAN DO
• Set up SUN with encrypted UID and counter, or plain mirroring
• Change the factory keys to random keys only you hold
• Verify a tag is genuine — signature and replay check
• Inspect how a secure tag is configured, no keys required
• Set up tags in batches, with duplicate detection
• Diagnose authentication and the secure channel step by step
VERIFICATION RUNS ON YOUR DEVICE
No account. No server. No ads. No analytics. No tracking. Your keys are stored in the iOS Keychain and sync through iCloud — they never reach us, because there is no "us" to reach. Verification works offline, which matters in a warehouse, a customs hall, or a venue with no signal.
PRICING WITHOUT A SUBSCRIPTION
Reading, writing, inspecting, and verifying are always free, and there are no ads anywhere in the app.
Set up your first secure tag for free, so you can confirm the whole thing works on your own hardware before paying anything. After that, Secure NFC Pro unlocks secure setup for good — one payment, no subscription, no renewals.
If a setup stops partway and leaves a tag half-configured, finishing that tag is free. The app started the change, so the app finishes it.
REQUIREMENTS
• iPhone 7 or later with iOS 17
• Tags that support SUN for the secure features
• Basic reading and writing work with any NDEF tag
NOTE ON WI-FI TAGS
Wi-Fi credentials are written to the standard Wi-Fi Simple Configuration format. iOS does not support automatic joining, so tapping the tag shows the network details instead of connecting.
CHANGING KEYS IS PERMANENT
These chips have no factory reset. If you lose a tag's keys, that tag can never be reconfigured. The app makes you confirm you've backed up your keys before it writes them, and keeps both the old and new keys until a change completes.
Ratings & Reviews
- This app hasn’t received enough ratings or reviews to display an overview.
The developer, Juyeon Yu, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Collected
The developer does not collect any data from this app.
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- Juyeon Yu
- Size
- 2 MB
- Category
- Utilities
- Compatibility
Requires iOS 17.0 or later.
- iPhone
Requires iOS 17.0 or later.
• iPhone 7
• iPhone 7 Plus
• iPhone 8
• iPhone 8 Plus
• iPhone X
• iPhone XS
• iPhone XS Max
• iPhone XR
• iPhone 11
• iPhone 11 Pro
• iPhone 11 Pro Max
• iPhone SE (2nd generation)
• iPhone 12 mini
• iPhone 12
• iPhone 12 Pro
• iPhone 12 Pro Max
• iPhone 13 Pro
• iPhone 13 Pro Max
• iPhone 13 mini
• iPhone 13
• iPhone SE (3rd generation)
• iPhone 14
• iPhone 14 Plus
• iPhone 14 Pro
• iPhone 14 Pro Max
• iPhone 15
• iPhone 15 Plus
• iPhone 15 Pro
• iPhone 15 Pro Max
• iPhone 16
• iPhone 16 Plus
• iPhone 16 Pro
• iPhone 16 Pro Max
• iPhone 16e
• iPhone 17 Pro
• iPhone 17 Pro Max
• iPhone 17
• iPhone Air
• iPhone 17e
• iPhone 18 Pro
• iPhone 18 Pro Max
• iPhone Duo
- iPhone
- Languages
- English
- Age Rating
4+
- 4+
- Copyright
- © 2026 Juyeon Yu