access to a remote service, some form of authentication, such as username/password authentication, is performed at the remote endpoint. No sensitive data should be stored locally on the mobile device. Instead, data should be retrieved from a remote endpoint when needed and only be kept in memory. If sensitive data is still required to be stored locally, it should be encrypted using a key derived from hardware backed storage which requires authentication. – OWASP MASVS 4.1, 2.11, 2.12 But what about deanonymisation? Non-custodial wallets are usually fat clients