Backup App (Emergency Access)
The backup app is a standalone emergency app, stored permanently on Arweave. It verifies Swap Cards and Tokentags, shows balances and sends funds – even when tokentagged.com is unreachable. Without Tokentagged servers, without login, without tracking, without cookies.
Main address: https://tokentagged.ar.io/ · Info page with current version, checksum and release wallet: https://tokentagged.com/backup
Save the address as a bookmark or on your phone's home screen – then you can find it even when tokentagged.com is unreachable.
What the backup app can do
| Function | Description |
|---|---|
| Verify | Check the authenticity of Swap Card and Tokentag: chip signature, manufacturer attestation, counter (nonce) and open approvals |
| View balances | Show the card's ETH, ERC‑20 tokens and NFTs – straight from the blockchain |
| Send | Send ETH and tokens from the card to another address. The card signs, the app forwards the transaction to the network |
| Activate a new Swap Card | Detect and activate a Swap Card that has not been activated yet – without the tokentagged.com web app |
| View‑only by address | Look at the balances and tokens of any address without tapping the card |
| QR code | Show the card's address as a QR code to receive funds |
Not included: buying cryptocurrency and minting certificates. For that you need the web app on tokentagged.com.
How it works
- A single file. The whole app is one HTML file that runs in the browser. You can also download it and open it locally.
- No Tokentagged servers, no login, no tracking, no cookies. The app never talks to Tokentagged servers. There is no account, no analytics script and no cookie.
- Data from public sources. Balances and transactions come directly from public Ethereum RPCs, token and approval data from Blockscout, images from Arweave and IPFS gateways. The list of sources is shown in the app's settings.
- Keys stay on the card. As in the web app, the private key is generated in the chip and never leaves it. The app only lets the card sign challenges and transactions – see Trust Chain & Key Generation.
The app relies on third‑party services (Arweave gateways, Ethereum RPCs, Blockscout). Their availability is not in our hands; the app therefore tries several sources one after another.
How to open it
- Main address: https://tokentagged.ar.io/ – the name "tokentagged" in the Arweave Name System (ArNS) points to the current version.
- Alternative gateways: the same name via other Arweave gateways (e.g.
tokentagged.arweave.net), in case one is unreachable – listed on https://tokentagged.com/backup. - Fixed address of a version: an Arweave transaction never changes;
https://arweave.net/<transaction>always opens exactly that version. The transaction IDs of all published versions are listed on the info page.
How to check authenticity
Only the addresses, checksums and the release wallet listed on https://tokentagged.com/backup are valid. Copies elsewhere may have been altered.
- Version number: the app shows its version under "About". Compare it with the current version on the info page.
- SHA‑256 of the file: on start, the app computes the checksum of its own file and shows it under "About". It must match the value on the info page. Download and check yourself:
sha256sum tokentagged-backup.html # Linux / macOS
certutil -hashfile tokentagged-backup.html SHA256 # Windows - Release wallet: every version is uploaded from the Arweave release wallet listed on the info page. The sender is part of the transaction.
- Transaction in the Arweave explorer: shows sender, tags (app name, version, checksum) and time of publication.
A file that does not come from one of these addresses or has a different checksum is not a Tokentagged backup app – even if it looks like one.
Versions
Every published version remains permanently reachable under its transaction. The version list (version, date, Arweave transaction, SHA‑256) is maintained on https://tokentagged.com/backup.
Supported browsers
| Platform | Browser | Notes |
|---|---|---|
| Android | Chrome | Reads the card via Web NFC – a single tap is enough |
| iPhone | Safari or Chrome | Reads the card via the security‑key path (WebAuthn). Hold the card to the phone once more in the second step |
| Android | Firefox or Brave | Also via the security‑key path. After reading, briefly remove the card and tap again |
Limits
- Checking open approvals relies on Blockscout. If Blockscout does not respond, the app cannot check this part and says so.
- Buying cryptocurrency and minting certificates are not included.
- The app relies on public third‑party services; their availability cannot be guaranteed.
Why this exists
Your certificate (Ethereum) and its data (Arweave) live outside Tokentagged's servers, and checking a chip needs only public information (chip signature, attestations, the SignerRegistry contract). The backup app makes this independence practical: any Swap Card or Tokentag can be verified and used without tokentagged.com. See Smart Contracts for the on‑chain side.