Object · spec · October 2026
A ring that hands over my card
Tap it to a phone and a page opens. The ring holds one address, written once. Where that address lands is one line on this site that I change from my desk.
At a glance
| What it is | A ring with a tiny NFC chip, the same kind of chip as in a tap-to-pay card. |
|---|---|
| What's on it | One web address, pi0.co/ringu. Written on October 9, 2026, and never rewritten. |
| Where it lands | Wherever I point that address. Right now it opens a short hello page with my writing, my work history and my shirts. |
| How it changes | One redirect line on this website. The ring itself never changes. |
| Works with | Most recent iPhones, and Android phones with NFC switched on. No app needed. |
| Status | In use since October 9, 2026. |
To read it
- iPhone: unlocked, screen on. Hold the ring near the top edge of the back of the phone. A banner appears; tap it.
- Android: NFC switched on in settings. Hold the ring near the middle of the back.
Make your own
- Get a ring with a writable NFC chip. Any NFC ring a phone app can write to.
- Pick an address you own and will never change. Mine is
pi0.co/ringu. It isn't a page; it's a forwarding address. Never write the final page onto the ring, or changing it means rewriting the ring. This step is the whole trick. - Write that one address to the ring with any NFC-writing app on your phone, as a web link. Then you're done with the ring.
- Point the address with a temporary redirect. On most website hosts this is one line, like
/ringu /card/ 302. Use 302, never 301: phones remember a 301 and keep going to the old page.
How it got this way
- Oct 9
- Wrote
pi0.co/ringuto the ring and pointed it at a contact card with a save-to-contacts file. - Oct 14
- Re-pointed for a panel event: the same card, framed for the room, with a prompt to try.
- Oct 16
- Re-pointed for a social night: a hello, my links, and the shirt shop. Same ring, no rewrite.
What it isn't
It isn't a payment ring, and it doesn't hold any of my data. The ring stores one address and nothing else. Everything you see after the tap is an ordinary web page.
No ring handy? See where mine points now.