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Meet ExtoWallet-

A new level of security and convenience 

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ExtoWallet consists of ExtoCard Hardware Wallets and accompanying iOS and Android App together providing a new level of security, convenience, and versatility for crypto-asset custody. 




ExtoCards provide on-card private fingerprint training and recognition along with backup Pin for added security.


Private-key generation for crypto accounts, transaction signatures, and keyword-based recovery is performed on the tamper-resistant card.


ExtoCards have secure Bluetooth, USB, and NFC communication capabilities to connect to phones, PCs, or each other. 

A touch Navigation Wheel and E-ink display enable secure means of authenticating transactions and recovery of the ExtoCard wallet key.

A USB dock allows recharging of the Card's Lithium battery which will last for weeks. 

In addition to passphrase recovery, ExtoCards can be securely duplicated using an encrypted Bluetooth link card-to-card. 

Biometric Recognition

Active capacitance sensor, large sensor area, protective coating for 10 million uses.


Compact ultra low power fingerprint recognition software and processing unit. 

Secure Elements

Secure Element hardware & firmware, for cryptographic algorithms with key, certificate and signature management.

Versatile User Interfaces

E-ink displays, LEDs, capacitive touch, and accelerometers enable versatile and easy to use interactivity 

Power Efficiency

Power management for extended battery life. 

USB or wireless charging options. 


Weeks of battery life between recharging. 

Tamper Resitance

Tamper Resistant, trusted design allowing storage of sensitive data

Flexible & Secure Applet Support

Ethernom's Biometric Smart Card Platform provides for a flexible and secure 3rd party App/ firmware development.

Trusted Edge Networking

Biometric Smart Cards load data when connected to backend systems,immutably store data when off network, and transact with other cards or devices in a trusted edge network using BLE/ NFC...

ExtoWallet App

ExtoWallet Apps- iOS, Andriod

ExtoWallet App.png

The ExtoWallet Apps provide secure and easy to use crypto wallet functions for both iOS and Andriod smartphones.  ExtoWallet Apps provide all user interfaces for transactions that need to be authenticated via the private keys stored on the ExtoCards.  

ExtoWallet Apps are based on a modified version of the proven BRD Wallet with millions of users and support Bitcoin, Bitcoin Cash, XRP, ETH, and many ERC20 Tokens. 




Secure Hardware Wallet and Mobile App-

ExtoCards provide a secure hardware wallet to store your private keys, authenticate crypto transactions, and recover lost wallets using 12 keywords, using a tramper resistant biometric smart card. In this fashion, no private account data needs to leave the secure enclave of the ExtoCards. In such a configuration, the ExtoWallet App provides easy to use user interfaces and means of connecting to the desired blockchains. Although no sensitive data is communicated to the ExtoWallet App, the Bluetooth connection between the card and the phone is encrypted and secure.  


Multi-Signatures made easy

For the ultimate security, multi-signature wallets can be set up where two co-signers will be required to authorize transactions. In this use scenario, both the ExtoCards and ExtoWallet Apps will create private keys and set up separate co-signing accounts requiring multi-signature from both devices. 

The cosigning options include:

  • Using your own ExtoCard and smartphone to cosign transactions. , or

  • Using two ExtoCards to cosign transactions. 

With ExtoWallet cosigning, your funds are protected by 2 private keys, one stored only on your card and one stored only on your phone.  Each device independently signs each transaction, so neither device can ever learn the key stored by the other.  Then the blockchain confirms that both signatures are correct before the funds can be moved.  How does the blockchain know what keys to use?  ExtoWallet makes that super simple.

  • For Bitcoin, you create a second cosigning wallet, which produces its own sequence of receive addresses, that can receive funds like any other Bitcoin address.  Then, if you try to spend any funds sent to that wallet, ExtoWallet will first demand your PIN code to authorize the phone signature, and then get a signature from the card.  Then the Bitcoin Network does the rest, with the same security that currently protects over $200B in assets.

  • For Ripple, it's a little different.  There remains only a single wallet with a single receive address, but you can turn co-signing on and off by submitting transactions to the Ripple blockchain.  Only the card signature is required to turn on cosigning.  Then both signatures are needed if you ever want to turn it off.  In between, every transaction requires a signature from both devices.

ExtoWallets simplify the process of creating and managing transactions for such multi-signature use scenarios. In both cases, the transaction fees are a little bit higher, but we think it is worth it for peace of mind. 


This combination of cosigning, the Biometric Authentication on the ExtoWallet Cards, and your Mobile device lead to 5-factor authentication where both devices would have to be compromised making it near impossible to attack.

(Cosigning Card+ Card Fingerprint)+ (Cosigning Phone + Phone Biometrics+ Phone Pin) = up to 5-Factor authentication.  


Cosigning supported for: 

Bitcoin and XRP

Bitcoin Cash, ETH, and ERC20 support coming soon

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The ExtoCards and ExtoWallet App allow the recovery of wallets and private keys with 12 keywords. 

If an ExtoCard is lost users can utilize the ExtoWallet App and many other software wallets to recover their accounts. 

ExtoCard duplicates can also be used as an added backup and recovery option. 


Users must record their 12 Keywords and Pins for their accounts in a safe location.

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