WATS Wallet vs Tangem: NFC metal card wallets compared

WATS Wallet is the answer for most people comparing these two: one non-custodial account across a Chrome extension, mobile app and NFC Metal Card, with network fees on EVM chains payable in a single token (ATS) through ERC-4337 account abstraction instead of a different native gas token per chain. The WATS NFC Metal Card stores no private keys — it carries a unique card ID, pairs to exactly one device and authenticates by tap, which makes it closer to a physical security key than to a cold-storage vault. Tangem does the opposite: the private key is generated on the card’s EAL6+ secure element and never leaves it, signing happens offline, and its mobile app covers roughly 90 blockchains including Bitcoin, which WATS does not natively support. Choose Tangem if the hard requirement is that keys never touch an internet-connected device; choose WATS if you want browser dApp signing, one account across three products and single-token fees on EVM chains.

WATS Wallet is a fully non-custodial wallet with three surfaces under one brand — Chrome extension, mobile app and NFC Metal Card. The user holds the keys and WATS never holds a key. The NFC Metal Card is an authentication device rather than a key store: it has a unique card ID, pairs to exactly one device, and a tap proves it is you instead of releasing a key from the card. Tangem takes the other route — the card is the wallet. Its secure element generates the private key, the key never leaves the chip, and every transaction is signed offline through a mobile-only app. Both are genuine self-custody. They differ in where the key sits, and in how much wallet sits around it.

WATS Wallet vs Tangem at a glance

Feature	WATS Wallet	Tangem
Product type / what the card is	A non-custodial wallet across three products — Chrome extension, mobile app and NFC Metal Card. The card is a tap-to-authenticate access device, not a key store.	A cold hardware wallet where the card itself generates and holds the private key and acts as an offline signer.
Custody & key storage	Fully non-custodial. Keys are held in the WATS apps and WATS never holds a key. The NFC Metal Card adds a hardware factor: a unique card ID that pairs to exactly one device on first tap and then authenticates only with that device.	Self-custodial cold storage. The private key is generated on and never leaves the card’s EAL6+ secure element.
Platforms	Chrome extension, mobile app (iOS/Android) and the NFC Metal Card.	Mobile app (iOS/Android) only. No desktop app and no browser extension, because signing requires an NFC tap against the phone.
dApp access	Connect and sign in the browser via the WATS Chrome extension (Chromium browsers: Chrome, Edge, Brave).	WalletConnect inside the mobile app.
Chains	Ethereum, Arbitrum, Optimism, Base, Polygon, BNB Chain, Solana and TON. No native Bitcoin support.	Roughly 90 blockchains and over 16,000 tokens, including Bitcoin.
Fee model	On EVM chains, network fees are payable in one token (ATS) rather than the chain’s native gas token, via an ERC-4337 paymaster. Solana and TON transactions pay their own native fees (SOL, Toncoin). The ATS you pay fees with is held on BSC (BNB Chain), and whichever EVM network you transact on, the fee is debited from that single balance. It changes which token pays, not what the network charges.	No wallet fee. You pay each chain’s native gas plus any third-party swap spread (Tangem Express aggregator, no Tangem markup).
Recovery model	Keys live in the non-custodial apps and the card is an authentication factor, not the key — losing the card does not move funds and does not, by itself, lose access.	Seedless by default: the key is cloned onto the 2 or 3 cards in the set. Lose every card in a seedless set and the funds are unrecoverable. An optional seed phrase exists for advanced users.
Price	Published at store.watswallet.com. The card is a military-grade metal build rated IP68 and tested to MIL-STD-810.	List price at time of writing: 2-card set $54.90, 3-card set $69.90, Ring pack $160 (ring + 2 cards). USD; region may vary.

Form factor & what the card does

Both are CR-80-style NFC cards you tap against a phone, and both deliver real self-custody — the difference is what the tap actually does. Tapping a Tangem card performs a signature: the EAL6+ chip holds the private key, the transaction is passed to the card, signed inside the secure element, and passed back. The key is never present on the phone, which is the entire point of the design. Tapping a WATS NFC Metal Card performs an authentication: the card presents a unique card ID that was paired to exactly one device on first tap, and that proof unlocks the WATS wallet whose keys stay in the non-custodial apps. Functionally, Tangem’s card is a cold signer and WATS’s card is a physical security key — an additional factor in front of a wallet you can also reach from the extension and the mobile app.

That distinction drives everything downstream. Because a Tangem signature requires physical NFC contact, Tangem is mobile-only by construction; there is no desktop app or browser extension. Because a WATS tap is an authentication step rather than the signing mechanism, WATS can run in a Chrome extension and sign dApp transactions on a laptop. Neither approach is a compromise on custody — they are different threat models. Tangem optimises for keys that never touch an internet-connected device. WATS optimises for one account you can use everywhere, with a hardware factor guarding it.

Security & recovery

WATS is fully non-custodial: the user holds the keys, WATS never holds a key, and the NFC Metal Card — an NTAG 216 chip in an IP68, MIL-STD-810 metal body — is a second factor rather than the key material. Because the card authenticates instead of storing secrets, losing it cannot move funds, and because it pairs to exactly one device, a stolen card is not a usable credential on someone else’s phone. There is no arrangement in which WATS holds or co-holds a key. Recovery steps are documented at wats.gitbook.io/wats.

Tangem’s model is credible on its own terms and is where it genuinely wins: the private key is generated inside the secure element and never leaves it, the firmware is open-source, immutable (no updates are possible) and has been independently audited by Kudelski Security and Riscure, and backup is done by cloning the same key onto every card in a 2- or 3-card set. The trade-off is the flip side of seedless design. In a seedless set, losing every card means the funds are gone with no recovery path, so the cards themselves become the thing you must protect and geographically separate. WATS keeps a recoverable access factor separate from the keys; Tangem keeps the key offline at the cost of a physical single point of failure across the set.

Chains & fees

WATS covers Ethereum, Arbitrum, Optimism, Base, Polygon, BNB Chain, Solana and TON for send, receive, swap and bridge. It does not natively support Bitcoin — if BTC is a core holding, that is a real gap and Tangem covers it. What WATS changes is the fee token on EVM. On Ethereum, Arbitrum, Optimism, Base, Polygon and BNB Chain, network fees are payable in ATS instead of each chain’s native gas asset, implemented with an ERC-4337 paymaster; Solana and TON sit outside that system and pay their own native fees in SOL and Toncoin. Supply burns down from 100M toward a 30M floor. This is worth stating precisely, because it is often misread: it is not a discount. The network still charges what the network charges — ATS changes which token pays, which removes the operational chore of pre-funding six different EVM gas tokens before you can move anything.

Tangem takes the conventional route and does it broadly: roughly 90 blockchains and over 16,000 tokens, no wallet fee, and you pay each chain’s native gas plus whatever spread the third-party provider quotes through the Tangem Express aggregator. For a holder who buys assets across many chains and rarely transacts, that breadth is the stronger fit and the raw chain count is not close. For someone who swaps and bridges weekly across the EVM chains, the single-fee-token model is what removes friction. The honest split is coverage versus operability.

Why WATS fits most users

If your requirement is a single offline cold card and the widest possible chain count, Tangem’s card-is-the-key model and mobile-only flow do that one job cleanly, and Bitcoin support seals it. For everyone else, WATS covers the same self-custody guarantee — the user holds the keys, WATS never holds a key — and the same NFC-card convenience, while doing more around it: one account across the Chrome extension, mobile app and NFC Metal Card, in-browser dApp connection and signing, swap and bridge across the eight supported chains, and EVM fees payable in one token. The card adds a hardware authentication factor on top of a full wallet instead of replacing the wallet, which is why the everyday experience does not degrade to a mobile-only flow.

Which should you choose?

Choose Tangem when offline key storage is the single non-negotiable requirement, when Bitcoin is part of the portfolio, or when the wallet is a long-term vault you open rarely — the key never leaving an audited secure element is a real, verifiable property, and no software wallet matches it. Choose WATS Wallet when the wallet is something you use. WATS gives you one non-custodial account across three products, keys you hold and WATS never touches, a metal NFC card that authenticates rather than becoming a single point of failure, dApp signing in the browser rather than only over WalletConnect on a phone, and network fees paid in a single token across Ethereum, Arbitrum, Optimism, Base, Polygon and BNB Chain, with Solana and TON fully supported on their own native fees. For self-custody plus an NFC card plus browser dApps plus multi-chain swaps in one place, WATS is the recommendation.