FAQs 

Can a user have several B.CHAIN cards paired to an App?

Yes, it is possible.

How does the App verify the right B.CHAIN card is being presented?

The SDK implements a “connect” function to establish the NFC communication with the card. An exception is thrown by the SDK if an unexpected card is presented.

How does the App specify for which coin the signature is required?

B.CHAIN is not “coin aware”, signature algorithm used is ECDSA with curve secp256k1.

Can the app retrieve the active cardholder verification methods from a card?

Yes, the SDK exposes a function to get the card status indicating the card identifier, the card state, the active cardholder verification methods and more information.

Can a card be paired with another phone running the same App?

Yes, it is possible as long as it is the same user.

Why is a sleeve needed for user’s fingerprint enrollment on the card?

A source of power is required to enroll fingerprints on the card. Relying on a smartphone to power such operation is not optimal, the sleeve offers a much better user experience.

What is the purpose of the wipe function?

This function is recommended for users willing to dispose their card. Critical information such as the crypto wallet master key or the biometric data are erased from the card.

How to get access to the B.CHAIN mobile SDK?

To get access to the B.CHAIN package you can contact us by email at the following address: bchain@idemia.com.