Tapsigner
NFC-enabled card from Coinkite storing a Bitcoin private key. Sign transactions by tapping the card to your phone.
Function
- Stores private key on a physical card with NFC communication
- Signs mobile wallet transactions via tap
- Works with compatible wallets supporting NFC signing
- No battery; passive NFC power from the device
Security Model
- Private key never leaves the card during signing
- Backup required during initial setup to prevent loss
- Two-factor: physical possession of card + wallet PIN/app
Comparison to SatsCard
| Feature | SatsCard | Tapsigner |
|---|---|---|
| Primary use | Transfer/gift sats | Sign transactions |
| Protocol | On-chain transfer | Signing |
| Reusability | 10 uses | Unlimited |
| Works with | Nunchuk | Multiple NFC wallets |
Manufacturer: Coinkite
See also: [sats-card], [bolt-card], [nunchuk]