Is your feature request related to a problem? Please describe.
Cake Wallet supports Ledger, Trezor, and BitBox over USB/Bluetooth, plus air-gapped signing with COLDCARD and Cupcake. All of them need a cable, a battery, or a second screen. There is no option for users who want a hardware wallet they can carry in a pocket without any of that.
Tangem cards sign over NFC. No battery, no cable, no pairing. Tangem also sells 2- and 3-card sets that hold the same key, so users get a backup that does not depend on storing a written seed. Today those users have to use the official Tangem app, which means no Cake Wallet UX, no exchange integrations, no Cake Pay, and no Monero.
Describe the solution you'd like
Add Tangem to the hardware wallet list under Restore Wallet, next to Ledger, Trezor, and BitBox.
Flow:
- User selects Tangem under Restore -> Hardware Wallet.
- Cake Wallet prompts for an NFC tap, reads the card's public keys, and derives addresses.
- Wallet syncs and shows balances as watch-only.
- On send, Cake Wallet builds the transaction and prompts for a tap. The card signs, Cake Wallet broadcasts.
- Access code prompts are handled by the SDK for cards configured with one.
Implementation notes:
- Tangem publishes an official Flutter plugin: https://github.com/tangem/tangem-sdk-flutter (pub.dev:
tangem_sdk). MIT licensed, and the underlying Android and iOS SDKs are open source.
- The SDK exposes generic primitives only: scan card, derive public keys via BIP32, sign hashes. There are no coin-specific applets, so all per-coin logic stays on the Cake Wallet side.
- Suggested first scope: Bitcoin and Litecoin (secp256k1), then Ethereum and Polygon. These map directly onto sign-hash-with-derived-key.
- Monero needs separate scoping. The Ledger integration relies on Monero-specific logic running in an on-device app. Tangem offers generic signing only, so key image generation and RingCT signing would need a different approach, and may not be possible without firmware support. Worth checking before committing to it.
- NFC works on both Android and iOS, so this can ship on both, unlike BitBox which is Android-only today.
Describe alternatives you've considered
- Official Tangem app. Works, but it is a separate wallet with separate UX. No Monero, no Cake Pay, no exchange flow. Funds end up split across two apps.
- Importing the Tangem seed into Cake Wallet. Only possible on seed-phrase cards, and it puts the key on the phone, which defeats the purpose.
- Buying a Ledger or Trezor. Valid, but a different product category. The point of Tangem is the card form factor.
- Air-gapped QR signing with Cupcake or COLDCARD. Good for cold storage, slower than one tap for regular spending, and needs a second device.
Additional context
Is your feature request related to a problem? Please describe.
Cake Wallet supports Ledger, Trezor, and BitBox over USB/Bluetooth, plus air-gapped signing with COLDCARD and Cupcake. All of them need a cable, a battery, or a second screen. There is no option for users who want a hardware wallet they can carry in a pocket without any of that.
Tangem cards sign over NFC. No battery, no cable, no pairing. Tangem also sells 2- and 3-card sets that hold the same key, so users get a backup that does not depend on storing a written seed. Today those users have to use the official Tangem app, which means no Cake Wallet UX, no exchange integrations, no Cake Pay, and no Monero.
Describe the solution you'd like
Add Tangem to the hardware wallet list under Restore Wallet, next to Ledger, Trezor, and BitBox.
Flow:
Implementation notes:
tangem_sdk). MIT licensed, and the underlying Android and iOS SDKs are open source.Describe alternatives you've considered
Additional context