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Apple has its eyes on your fingertips, for security apps

However, if you are going biometric, most installations are part of two-factor authentication. In this case, it would still mean typing in a pin. Why? Lets say you lost a phone with fingerprint scanning. If the finder is careful, the owner's fingerprints are all over the the phone and can be lifted and used for authentication. You still really need something else, even if it is just a pin.