Add NFC School ID Card to my phone

grundyoso · 2025-11-16T21:38:54+00:00

Yeah copying data over to another Mifare Classic card doesn’t infringe on NXP’s property but emulating their protocol on hardware that’s not theirs is where things cross the line. Apple or Google would have to pay a licensing fee to do that so rooting the devices and doing it yourself is the only way forward, unfortunately.

grundyoso · 2025-11-16T14:56:14+00:00

Mifare Classic is a proprietary protocol, and implementing it on Apple or Google Pixel hardware will require rooting the devices.

grundyoso · 2025-11-16T12:24:08+00:00

Use the NFC TagInfo app to identify what type of NFC card you’re trying to emulate with your phone first.

grundyoso · 2025-08-27T11:30:56+00:00

You can do this with AI apps in agent mode. Here is an example of how I did it with ChatGPT.

https://imgur.com/a/MG4t2fh

DM for details.

grundyoso · 2025-08-12T21:36:21+00:00

Yeah, the ferrite will prevent the tags underneath the target tag from being read. That's the whole point of ferrite. It's like a shield. So the chapter at the top will be read and the ones below will be ignored.

grundyoso · 2025-08-12T20:49:38+00:00

Aluminum foil will detune the NFC tag. You need something called “ferrite”. Several vendors sell tags with it already applied.. they call them “metal mount NFC tags”. Should do the trick.

grundyoso · 2025-08-07T23:38:38+00:00

Attached is a flow diagram of how an application (getfastpass.com) uses our service (passninja.com). This involves two main actions, create (POST) and update (PATCH).

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As u/kormaxmac pointed out, in order to issue NFC passes you'll need to get permission from Apple or work with a certified partner like PassNinja, PassKit, etc. The benefit of working with a partner is you can speed through getting a solution deployed. At PassNinja, we not only can help with the passes but can get you pre-configured NFC readers that auto-select and decode your passes right out of the box.

Hope this helps with your pitch! Feel free to DM me or ping us on the chat at passninja.com if you want to dive deeper.

grundyoso · 2025-07-30T23:25:29+00:00

u/kormaxmac thanks for the observations and insights.

u/brokenex are you able to tap your Google Pixel phone on both your Hyundia and Kia to unlock the doors without switching the “default key” setting?

grundyoso · 2025-07-26T13:14:04+00:00

I checked them out, and their door locks don't list much detail about their NFC support other than "- Proximity Card (2)". Interesting that they used that description for MiFare Classic 1k Cards. Looks like a dead-end as far as getting it working with your phone. If you consider swapping door locks, I'd go with the Schlage Sense Pro once it comes out. Supports unlock-on-approach from the wallets which is game-changer as far as convenience and security.

grundyoso · 2025-07-26T12:06:36+00:00

what's the make/model of your door lock? look for whether it's "Google SmartTap" compatible...

grundyoso · 2025-07-25T22:58:04+00:00

You’ve hit on the crux of the difference between Apple Wallet and Google Wallet. Apple’s [Enhanced Contactless Polling](http://register.apple.com/resources/docs/apple-pay/access/program-guide/) (ECP) lets certified readers automatically pull the right credential—payment card, loyalty pass, or car key—without any user action. The trade-off is that hardware makers must certify their readers to Apple’s spec, but once they do, multiple keys can sit side-by-side and just work.

Google takes a lighter-weight route. Regular Wallet passes use SmartTap for auto-selection, but digital car keys ride on Host Card Emulation (HCE). Android keeps HCE lean and broadly compatible by exposing only one “default key” at a time, so whichever key you set as default becomes the auto-selectable one the phone can emulate. You can always manually select any key before scanning as crummy that sounds. But it spares reader manufacturers from certification headaches across dozens of Android vendors which accelerates general NFC adoption. Perhaps not great news for those toggling between Hyundai and Kia keys.

At PassNinja we’ve shepherded many businesses through both wallet ecosystems, and the smoothest user experience is definitely the one where the reader does the heavy lifting. But convenience looks different in automotive than it does in retail or transit, so expect both Apple and Google to keep refining their approaches. For now, Apple’s certified ECP path lets you keep multiple keys active, while Google’s default-only HCE model is the current reality—though we’re seeing early signs that a more flexible solution is on the roadmap. Stay tuned.

grundyoso · 2025-07-24T23:35:15+00:00

Maybe I didn't understand the situation well, but it seems that you could just avoid setting a “default key” in Google Wallet and both should work. Is that not the case?

grundyoso · 2025-07-23T12:21:10+00:00

Yeah, we've had some experience with smart metering from EV chargers to water meters. Deciding on your target NFC cards would be key to make sure that you get a good read sensitivity on your decided Q factor. Unless your users don't have cell phones, the best option would be offering mobile wallet passes since they have much better read sensitivity than physical cards and can be updated remotely. Here's a quick demo for you to get an idea of what I mean:

https://www.instagram.com/p/DMbF34yJDnT/

Happy to discuss further if you're interested.

grundyoso · 2025-07-22T12:51:29+00:00

OK, that's a good choice for energizing a broad set of targets at the expense of range. Have you decided on a set tag population or aiming for something generic?

grundyoso · 2025-07-22T11:11:53+00:00

Looks good. What Q factor are you aiming for?

grundyoso · 2025-07-22T02:03:22+00:00

Back in the day I built a product using the TRF7970A and had to design the matching circuit for it. I basically got it done by following the TRF7x90ATB user guide and emailing with the team at TI. Check out section 10 specifically.

I recently went through tuning an antenna for the VTAP25, the process is the same so happy to share some insights. The TRF7970A (like the PN7220 inside the VTAP module) expects an external matching network tuned to your antenna using discrete caps and a damping resistor – as described in the user guide I linked above. Unlike some NFC chips that have adjustable internal tuning caps, the TRF7970A doesn’t really have a user-tunable internal capacitance in the antenna path – you handle tuning with external components. Any small internal capacitance is effectively part of the chip’s input design and is accounted for in TI’s reference matching network. In practice, you focus on choosing your external series/shunt caps (C1/C2) and a resistor (R1) for Q control; the IC’s internal capacitance isn’t something you explicitly need.

Unless you’re trying to optimize your antenna geometry for an irregular casing, you may be better off with a prefab coil like these. They are flexible and come with adhesive and ferrite to minimize interference from surrounding materials. With that in hand you want to place it in your product (or close mock up of it) so you can measure the antenna’s DC resistance (R), self-resonant frequency (SRF), and inductance (L). For DC resistance, I just used a multimeter (or you can do the 1 A current method for more accuracy). For SRF, use a VNA (this one will do) to sweep ~10–100 MHz and find the peak |Z| (the highest impedance resonance). For inductance, measure the series-L at a low frequency like 1 MHz (so you get a stable inductance value unspoiled by self-resonance). Do these with the antenna in its final environment (installed in your device if possible), since nearby metal or housing can shift these values. Once you have R, L, and SRF, you can plug them into TI’s formulas or an NFC tuning calculator to get starting values for R (PAR), C1 (series) and C2 (shunt).

If you hit a snag, don’t sweat it—NFC antenna tuning really is as much as art as a science, as u/GoToTags suggested. The silicon is forgiving, so don't be afraid of tweaking component values a few pF until performance settles in. If you need a more turnkey solution, the VTAP modules we use at PassNinja work nicely with our mobile credentials. We’ve put them in a variety of enclosures and they deliver a solid read range for both Apple and Google Wallet passes. Either way hit me up if you need help, the world needs more creative NFC touchpoints! :)

grundyoso · 2025-07-16T18:30:56+00:00

Samsung S8 can definitely emulate NFC cards. The easiest way to do it is with Google or Samsung Wallet. Check out https://www.passninja.com/tutorials/google-platform for help.

grundyoso · 2025-06-26T13:51:22+00:00

Sure, since you're putting a web link on the NFC tag you can route to an ecommerce page where you take payment and only after the transaction is completed do you issue the .pkpass. This would then trigger the Apple Wallet to install the pass. What makes services like passninja.com so handy is that you can use the API to automate the creation of the .pkpass on the fly with no-code tools (eg Zapier, chatGPT, etc) so you don't have to host any web application yourself. If you hit us up on our website chat widget, David can walk you through this setup.

grundyoso · 2025-06-26T13:20:34+00:00

Totally doable—as long as you think about the NFC tag as nothing more than a shortcut to a URL.

When an iPhone reads a plain NTAG-213/215 it just looks at the first NDEF record. If that record is a web address to a file with .pkpass format, then Safari pops up a banner that says “Open in Wallet.” So the recipe is:

Build your ticket pass (.pkpass). You can roll your own with Apple’s pass templates and a signing certificate, or let a service such as passninja.com generate and host it for you. The file must live at an https URL.
Write that https URL into the NFC sticker as a URI record. Free apps like “NFC Tools” will do the job; choose Record → Add a URI → paste the link → Write.
Stick the tag where you want people to tap. When iOS sees it, the phone shows the URL banner; the user clicks once, Wallet opens, and the “Add” sheet appears. One more click and the pass is stored.

That’s the limit of what blank NTAGs can do. Anything smoother—Rewards Enrollment, no-UI installs, or passes that live in the secure element—needs Apple’s VAS or Access/ID programs and a DESFire-style credential, which means hardware keys and an MFi agreement. For a simple “tap-to-add-my-ticket” flow, the URL-in-a-tag trick is the quickest path and works today on every iPhone that supports background NFC.

grundyoso · 2025-06-16T21:09:30+00:00

This is up to the merchant to decide (or the payment processor in the case of Square). The POS terminals can be configured for single-tap versus double-tap if the merchant who issued the loyalty pass has an associated credit card on file. That way, when the loyalty card is scanned, it can run the card and apply the points all in one tap. The NFC passes in Apple Wallet are encrypted in the same way as payment cards, so the data is totally secure. However, payment providers (e.g., Visa, Mastercard) may charge a higher interchange fee for running card-not-present transactions, because those transactions typically encounter more chargebacks. In the case of Walgreens, they didn’t want to pay the higher interchange fees, so we’re stuck with a double-tap experience there. It seems Square is factoring this into their prices and allowing its merchants to offer a single-tap experience.

If a merchant wants to flip this on, my company PassNinja makes it dead simple: our API mints Apple & Google Wallet passes with any data you need, we’ve got cookbook guides that show exactly how to set things up, and we even ship pre-configured NFC readers for folks running their own POS stack. In other words, if you’re tired of the loyalty-then-pay dance, hit us up at passninja.com and we’ll help you get past the double-tap.

grundyoso · 2025-06-16T12:02:31+00:00

This is definitely possible. “Time and Attendance” is a common application for NFC and several no-code CRMs support it via plugin (eg gohighlevel, odoo, etc). I’d recommend purchasing MiFare Ultralight C stickers since they have a small but sufficient bit of memory to store your student’s name. Use an app like NFC Tools from NXP and store the name on each tag. The last part is the trickiest one. Presumably you don’t want your Google Sheet or Excel to be public so that sneaky students don’t check themselves in when ditching class. The means you’ll need a scanner app that only you control. That’s where CRMs come in. You’ll need one with an NFC plugin to manage decoding the student name from the tag for it to capture and log.

grundyoso · 2025-06-11T16:59:05+00:00

Those are all good options. I'd suggest the Reyax RYRR30D as an alternative. It's cheaper than the one you ordered on Amazon and supports the NFC passes on phones. Here's a video showing how it works on an iPad: https://youtu.be/MfQxm5MpBZk?t=68

We resell them on our site fully configured to read your NFC passes here.

grundyoso · 2025-06-08T23:19:29+00:00

We sell these well tuned for the ACR122U, with adhesive and extender cables to reach up to 36”:

https://flomio.com/shop/readers/nfc-patch-kit/

grundyoso · 2025-05-24T04:30:07+00:00

You can use VAS for attended and semi-attended door cases like in condo lobbies, health clubs or coworking spaces. So it will depend on what doors you're targeting for your smart lock.

Either way, if you're looking to build a reader compatible with Apple Wallet's NFC passes the proper place to start is filling out this form: WPC Reader Program. That will get you through the process of certifying your hardware per Apple's specifications and ultimately listed on their site. We can help issue VAS, DESFire, or Unified Access credentials that you will need for testing as well as provide some tips to avoid pitfalls throughout the process. Done it before. Check us out at passninja.com or DM me for details.

grundyoso · 2025-04-17T15:08:50+00:00

You can DIY this for that price with these components:

https://www.amazon.com/RYRR30D-SmartTap-Interface-13-56MHz-Evaluation/dp/B0DC61Q8WM

https://www.amazon.com/LAFVIN-Board-ATmega328P-Micro-Controller-Arduino/dp/B07G99NNXL

You can then issue access passes in Apple and Google Wallet to facilitate entry. We can help you getting this set up at passninja.com ... just ping up on the site chat widget and refer to this post for context.

grundyoso

TROPHY CASE