You can use biometric auth. for signing transactions. While this is a little less secure than signing with a long passphrase, it makes a lot of sense for every day payments and accounts with a relatively lower balance.
You can select the security type on a per account basis after importing or generating the account.
When selecting Standard security, you can use your PIN, Fingerprint of FaceID.
If you select Extra security you can only use a strong passphrase.