Device-specific hardware settings
Touch ID in the side button
Most people call this the fingerprint reader built into the power button.
On the iPhone Duo the fingerprint sensor is built into the side button rather than a Home button, so you rest your finger on the button you already press.
This setting is present on your iPhone.
- We have this path on file but have not yet confirmed it against an official source.
Where to find it - iOS 27 and later
- Settings
- Touch ID & Passcode
What it does
It works the same way as a Home button sensor: several fingerprints can be enrolled, and it authorises unlocking, Apple Pay, purchases and password filling. A foldable design leaves no room for a Home button, and the front is display, so the side button is where the sensor fits.
What changes
When it is on
Resting a finger on the side button unlocks the phone.
When it is off
Everything falls back to the passcode.
Should you turn it on?
Good reasons to turn it on
- Works with the phone folded or unfolded.
- Reliable when your face is covered.
- Enrol the fingers you naturally rest on the button.
Good reasons to turn it off
- You would rather no fingerprint data existed on the device.
Battery
No real change
Privacy
Helps
Performance
No real change
Cellular data
No real change
Storage
No real change
Out of the box: Offered during setup on models with the sensor.
Worth reading first
What your iPhone needs
- Only on iPhones with Touch ID in the side button
Questions people actually ask
- Does the iPhone Duo have Face ID?
- No. It uses Touch ID built into the side button.
- Where is the fingerprint sensor on the iPhone Duo?
- In the side button, the same one you press to lock the screen.
If it is not working
- Enrol the same finger twice at different angles for a more reliable read.
- Rest the finger, do not press hard. Pressing locks the screen instead.
- The phone has no Face ID, so there is no alternate appearance to configure.