When a user creates a wallet in a non-custodial wallet app, the app typically prompts the user to back up the associated private key. This private key is usually presented as a 12 or 24-word list, known as a mnemonic phrase or seed.
The wallet owner is responsible for securely storing this phrase offline and using it to restore access to the wallet in scenarios like smartphone loss or theft.
While there are valid security reasons for keeping mnemonic phrases offline, there are also risks associated with this approach. If the phrase is discovered by someone knowledgeable about its purpose, they may easily gain unauthorized access to the wallet funds.
To enhance private key security and minimize the risk of unauthorized access, one approach is to add a mnemonic passphrase. Panaroma Decentralized wallet app provides this feature.