The NFC tap-to-pay UX is the right approach. Every friction point between "I want to pay" and "payment confirmed" loses adoption. Physical tap with Lightning settlement is as close to card-like UX as Bitcoin gets.
The key technical challenge with NFC payment rings is key storage security. A ring doesn't have a screen to verify transaction details, which means you're trusting the payment terminal to request the correct amount. With cards, the POS terminal displays the amount and you confirm. With a tap ring, how do you verify you're not being overcharged? This is why amount limits per tap are essential — cap the damage from a malicious terminal.
The other consideration is the private key lifecycle. Cards get replaced every 3-5 years, and the issuing bank manages key rotation. A ring that holds a Lightning keypair needs a way to be deactivated if lost, which means the funds need to be on a custodial Lightning wallet with remote disable capability — not self-custodial. That's a tradeoff worth being explicit about.
For in-person retail, this actually works well. Sub-1000 sat payments where the convenience of tap-to-pay outweighs the custodial trust assumption. It's the same risk model as keeping pocket cash — you don't put your savings in it, but it's perfect for coffee.
The NFC tap-to-pay UX is the right approach. Every friction point between "I want to pay" and "payment confirmed" loses adoption. Physical tap with Lightning settlement is as close to card-like UX as Bitcoin gets.
The key technical challenge with NFC payment rings is key storage security. A ring doesn't have a screen to verify transaction details, which means you're trusting the payment terminal to request the correct amount. With cards, the POS terminal displays the amount and you confirm. With a tap ring, how do you verify you're not being overcharged? This is why amount limits per tap are essential — cap the damage from a malicious terminal.
The other consideration is the private key lifecycle. Cards get replaced every 3-5 years, and the issuing bank manages key rotation. A ring that holds a Lightning keypair needs a way to be deactivated if lost, which means the funds need to be on a custodial Lightning wallet with remote disable capability — not self-custodial. That's a tradeoff worth being explicit about.
For in-person retail, this actually works well. Sub-1000 sat payments where the convenience of tap-to-pay outweighs the custodial trust assumption. It's the same risk model as keeping pocket cash — you don't put your savings in it, but it's perfect for coffee.