Privacy Policy

Twenty One Wallet (21W)

Last updated: June 16, 2026

21W is a self-custodial Bitcoin mobile wallet. This policy describes how the app handles information. We designed 21W so you can use it without creating an account with us.

Summary

• No account is required to use 21W.
• We do not run analytics or advertising in the app.
• We do not operate a 21W backend that stores your wallet or recovery phrase.
• Your recovery phrase stays on your device and is not sent to us.

Information we do not collect

21W does not ask you to sign up and does not collect:

• Your name, email address, or phone number inside the app
• Your recovery phrase or private keys
• Contacts from your address book
• Precise location
• Usage analytics, crash reporting tied to your identity, or advertising identifiers

Data stored on your device

Wallet data is stored locally on your phone. Depending on how you use the app, this can include:

• Recovery phrase — stored in the device secure storage (iOS Keychain / Android Keystore) with authentication required when supported.
• Wallet state — Ark wallet and Lightning swap records in a local SQLite database on the device.
• Preferences — non-sensitive settings such as biometric unlock preference and UI reminders, stored locally.
• Cached display data — recent balance or activity preview data cached locally for faster loading.

If you delete the wallet in Settings, local wallet data managed by the app is removed from the device. Anyone with your recovery phrase can restore the wallet elsewhere.

Network connections

To send and receive Bitcoin, the app connects directly from your device to public network services. We do not proxy your traffic through a 21W server. Current connections include:

• Ark network (arkade.computer) — wallet operations on Bitcoin mainnet.
• Bitcoin block explorer API (mempool.space) — chain data used by the wallet software.
• Lightning swap services — accessed through the Ark/Boltz libraries when you fund from or withdraw to Lightning.
• Fiat exchange rate (api.coingecko.com) — optional display of an approximate local-currency equivalent. Requests are initiated from your device and are not linked to a 21W account.

Those services receive network requests needed to perform the action you request (for example, broadcasting or monitoring transactions). Their own privacy practices apply to data they process.

Device permissions

• Biometrics / device authentication — used to protect sensitive actions such as revealing your recovery phrase, confirming sends, or unlocking the app when you enable that option.
• Camera — used only when you scan a payment QR code. Images are processed on device for decoding and are not uploaded to 21W.

Your responsibilities

21W is experimental software. You are responsible for securing your device, backing up your recovery phrase offline, and verifying addresses and amounts before sending Bitcoin. We cannot recover a lost recovery phrase.

Children

21W is not directed at children under 13, and we do not knowingly collect personal information from children.

Changes to this policy

We may update this page when the app changes. The “Last updated” date at the top will change when we do. Continued use of the app after an update means you accept the revised policy.

Contact

Questions about this policy: support@21w.app

For help using the app, see the support page.