Overview
Keystone is a hardware wallet that does something most others don't: it never connects to your computer or phone at all. No USB cable, no Bluetooth, no WiFi, no NFC. Instead, you point its built-in camera at your phone or laptop screen to read a QR code, and beam the signed transaction back through another QR code. Because the device is fully "air-gapped" (cut off from any network), hackers who try to attack it through USB or Bluetooth have nothing to attack1.
The flagship Keystone 3 Pro device supports Cardano (ADA) along with Bitcoin, Ethereum, XRP, Solana, and dozens of other coins. It pairs with most of the main software wallets, including Cardano's own Eternl, plus MetaMask, Rabby, and OKX2.
Key Features
- No USB. No Bluetooth. No WiFi. No NFC. The device communicates only through QR codes scanned by its built-in camera, so there's no wired or wireless attack surface to exploit1.
- A four-inch touchscreen. Big enough to clearly show every transaction's full details before you approve it, with a fingerprint sensor for unlocking1.
- Three secure chips inside, plus tamper detection. Three separate chips work together to lock down your keys, and an extra physical safeguard wipes the device if someone tries to crack it open3.
- Software anyone can inspect. Keystone publishes its code on GitHub, written mostly in a memory-safe language called Rust. Anyone with the technical skills can review what runs on the device4.
- Up to three wallets on one device. Useful if you want to separate, say, your everyday spending wallet from your long-term savings without buying two devices1.
- Works with the main Cardano wallets. Pair with Eternl through QR code signing to manage ADA, stake, and use Cardano apps2.
What to Expect
Setting up a Keystone takes around ten minutes. You unbox the device, power it on (it runs on regular batteries), generate a 12- or 24-word recovery phrase on the touchscreen, and write the phrase down on paper. You can also use a steel backup plate if you're worried about fire or water damage.
Day-to-day, you keep the Keystone offline somewhere safe. When you want to send a transaction, you open a software wallet on your phone or laptop, build the transaction there, and it shows a QR code. Hold the Keystone in front of the QR code; the device's camera reads it, the screen shows the full transaction details, you check it with your fingerprint, and the device displays a new QR code with the signed result. You scan that with your phone, and the transaction goes out to the network. Sounds elaborate, but in practice it takes about thirty seconds and feels closer to scanning a boarding pass than to setting up a router.
For Cardano specifically, pair Keystone with a Cardano wallet that supports QR signing (Eternl is the main one). The wallet handles your balance, staking, and Cardano app sign-ins as usual; the Keystone just signs the transactions when needed. Keystone descended from the earlier Cobo Vault product and has had its code reviewed by independent security firms including SlowMist, Offside Labs, and BlockSec2.
