A simple directory of the best Bitcoin signing devices, metal seed backup tools, and supporting wallet software — because your sats are best stored cold.
Nunchuk
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Nunchuk
Cross-platform Bitcoin multisig wallet. Inheritance with on-chain timelocks, air-gapped signing, 10+ hardware wallets, and collaborative custody. Desktop and mobile.
Nunchuk is a cross-platform Bitcoin wallet built from the ground up for serious multisig custody and Bitcoin inheritance planning. Its defining feature is autonomous inheritance using on-chain timelocks — Bitcoin passes to heirs automatically without trusting any company or server. Nunchuk supports 10+ hardware wallets including Coldcard, Tapsigner, Blockstream Jade, Ledger, Trezor, SeedSigner, BitBox02, Portal, Foundation Passport, and Keystone, with air-gapped signing via QR codes and SD cards. Features include multi-user collaborative wallets, decoy wallets, advanced coin control, and emergency lockdown. Private keys never leave your hardware devices. Nunchuk is designed to outlive the company that created it: all wallet data is stored locally, and recovery never requires Nunchuk's servers. Zero KYC. Available on macOS, Windows, Linux, iOS, and Android. Open source on GitHub.
