Tangem

Tangem is a cold wallet built into a plastic smart card, not a cable-connected USB stick. The card holds a secure chip that creates your private keys the first time you set it up; those keys are sealed inside the chip and cannot be read out, copied or exported. To use it you open the Tangem app on your phone and tap the card to the back of the handset over NFC — the same contactless technology as a payment card — then confirm with a passcode or biometrics. Because the card has no screen and no battery, you review and approve each transaction on the paired phone rather than on the device itself.

Tangem sells the wallet as a set of two or three identical cards, and also offers the Tangem Ring, a wearable that works the same way by tap. There is nothing to charge and nothing to plug in; the card is dormant until it touches a phone.

The chip at the centre of a Tangem card is a Samsung secure element certified to Common Criteria EAL6+, a level used for banking and passport chips. Keys are generated on the card and never leave it, so an attacker who cannot physically break the certified chip cannot lift them off — and Tangem's firmware and app have been through public third-party audits. The card has no online component of its own, which removes the whole class of remote-drain attacks that target internet-connected wallets.

The design trade-off is recovery. By default Tangem uses no seed phrase; instead your backup is the set of linked cards you bought, which you keep in separate places. That means there is no 24-word phrase for a phisher to steal — but it also means that if you lose every card in the set and never enabled the optional seed export on the newer cards, there is no way back to the funds. Understanding that backup choice up front is the main thing to get right with Tangem.