The Auto-Reply Flaw
When you receive an incoming phone call on a locked iPhone, the screen displays a “Message” button. This allows you to quickly decline the call and instantly send a pre-written text (like “Can’t talk right now”) to the caller. However, this is a significant privacy loophole. Anyone who picks up your ringing, locked iPhone can tap that button and send those generic texts on your behalf, without ever needing your Face ID or passcode. If you want to guarantee that your phone can never send outgoing messages while locked, you must disable this feature.
How to Turn Off Reply with Message
You can permanently hide outgoing texting capabilities behind the passcode wall via the Face ID settings.
- Open the Settings app on your iPhone.
- Scroll down and tap on Face ID & Passcode (or Touch ID & Passcode).
- Enter your device’s master PIN code to access the secure menu.
- Scroll down to the section labeled “Allow Access When Locked.”
- Locate the toggle switch labeled Reply with Message.
- Toggle this switch to the Off position (the green background will disappear).
Secured Communication
The change takes effect instantly. The iPhone will completely sever the texting API from the locked incoming call screen. When your phone rings while locked, the “Message” button will either disappear entirely or, if tapped, will instantly prompt for Face ID or a passcode before allowing the text to be sent. This guarantees that your phone can never be used to initiate any form of outbound communication—even pre-written templates—without your explicit, biometric authorization.