Travel to your private keys and leave your laptop at home.
Hellbender is an iOS Bitcoin multisig coordinator written in Swift. It operates as a watch-only wallet — private keys never touch your phone. Coordinate signing across air-gapped hardware wallets using animated QR codes, bringing cold storage security with mobile convenience.
- Watch-only architecture — only public descriptors are stored on the device
- Air-gapped QR signing — UR and BBQR animated QR codes for PSBT exchange
- Configurable M-of-N multisig — 2-of-3, 3-of-5, and beyond
- Full BIP-174 PSBT workflows — create, sign, combine, and broadcast
- UTXO management — coin control and coin freezing
- RBF fee bumping — replace-by-fee support for stuck transactions
- Multi-network support — mainnet, testnet3, testnet4, and signet
- Biometric security — Face ID / Touch ID lock
- Descriptor import/export — QR scan, clipboard, and PDF export
- Electrum server integration — connect to your own node or a public server
- Multi-wallet profiles — manage multiple wallets in one app
- Xcode 16.2+
- iOS 18.6+ deployment target
- Swift 5.0
All dependencies are managed via Swift Package Manager and resolve automatically:
| Package | Purpose |
|---|---|
| BitcoinDevKit (bdk-swift) | Bitcoin operations |
| URKit | UR encoding/decoding |
| URUI | QR display and scanning |
| Bbqr | BBQR encoding |
- Clone the repository
git clone https://github.com/newtonick/hellbender-wallet.git cd hellbender-wallet - Open
hellbender.xcodeprojin Xcode - SPM dependencies resolve automatically on first open
- Build and run on a simulator or device
GitHub Actions runs xcodebuild clean build analyze on every push and pull request to main.
- Website: hellbenderwallet.com
- TestFlight Beta: Join the beta
- Author: newtonick
MIT License — see LICENSE for details.
Hellbender's dependencies use permissive licenses compatible with MIT: bdk-swift (MIT/Apache-2.0), URKit (BSD-2-Clause-Patent), URUI (BSD-2-Clause-Patent), Bbqr (Apache-2.0).
