Coldcard MK4
COLDCARD Mk4 with upgraded secure elements, USB-C connector, new plastic, optional NFC, massive RAM for multisig, and much-much more.
Webshop
Tapsigner
Wireless NFC smart-card that holds your Bitcoin private key (XPRV) and will sign transactions with a simple tap on your phone. Compatible with wallet apps like Nunchuk (iOS, And...
Order summary
Ready to add this?
Review price, shipping and options before adding it to your cart.
Overview
- Wireless NFC smart-card that holds your Bitcoin private key (XPRV) and will sign transactions with a simple tap on your phone.
- Compatible with wallet apps like Nunchuk (iOS, Android, Desktop) and Sparrow (Desktop)
- Verifiable entropy, meaning you know 100% that no one but the TAPSIGNER itself has the private key that controls the Bitcoin.
- Can be easily – and securely – backed-up into a file.
Details
What is TAPSIGNER?
A simple Bitcoin wallet in your pocket. Think of it as a Bitcoin private key on a card! You can sign mobile wallet transactions by tapping the card on your phone. Your mobile wallet provides most of the wallet logic and TAPSIGNER holds the secrets. It’s essentially a hardware wallet you can slip inside your regular wallet.
What app can I use with my TAPSIGNER?
Sparrow – Desktop
What’s the motivation for TAPSIGNER? There is already the COLDCARD.
- TAPSIGNER’s lower cost makes hardware wallet features and security available to a wider market around the world.
- An NFC card provides fast and easy user experiences.
- TAPSIGNER is a great way to keep your keys separate from your wallet(s).
- Card form factor makes it easy to carry and easy to conceal
What are some possible uses for TAPSIGNER?
- Phone wallet cosigning
- Opening and closing Lightning Network channels
- Using an NFC module with a Lightning Network node
- Message signing
- Collaborative multisig service applications
- Raw transactions
- Partially signed Bitcoin transactions (PSBTs) via HWI
- App Authentication
Explainer in English by Bitcoin Sessions: https://www.youtube.com/watch?v=xKHy1HMw5iU
Explainer in Dutch coming soon.
