The iPhone Duo utilizes Touch ID integrated into its side button for authentication. Initially, unlocking requires fingerprint verification followed by a swipe up on the Lock Screen. However, a setting called "Rest Finger to Open" can bypass this swipe. This feature allows immediate access to the iPhone by simply resting a finger on the side button after it's awake. The "Rest Finger to Open" toggle can be found in two locations within the Settings app. These are under "Touch ID & Passcode" and "Accessibility" via the "Side Button" menu. Both locations lead to the same setting, confirmed by Apple's description. If the user prefers the traditional swipe, they can easily disable this setting. Disabling it will revert the unlocking process to requiring a swipe after fingerprint authentication.