Works for ZERO Messenger whether or not it has its own passcode. No download needed.
Touch and hold ZERO Messenger's icon, tap Require Face ID, then confirm. On iOS 18 and later that puts ZERO Messenger behind Face ID, Touch ID or your passcode; choose Hide and Require Face ID instead to move it into App Library's Hidden folder as well.
Lock ZERO Messenger with Face ID
- Find ZERO Messenger on your Home Screen or in App Library.
- Touch and hold the icon until the quick-actions menu opens.
- Tap Require Face ID (or Require Touch ID / Require Passcode, depending on your iPhone).
- Tap Require Face ID again to confirm. ZERO Messenger now asks for authentication every time it opens.
To test it, close ZERO Messenger from the App Switcher and open it again. You should see the Face ID prompt before any content appears.
Hide ZERO Messenger in App Library
- Touch and hold ZERO Messenger's icon and tap Require Face ID.
- Choose Hide and Require Face ID instead of Require Face ID.
- Confirm. The icon leaves your Home Screen and moves to the Hidden folder at the bottom of App Library.
- To open it later, swipe to App Library, tap Hidden and authenticate.
Hiding also locks the app. To undo either, touch and hold the icon again and choose Don't Require Face ID.
Why lock ZERO Messenger?
ZERO Messenger is a secure messenger, the kind of app that tends to hold personal information you would not want on screen if someone borrows your unlocked phone. Messengers see who you talk to as well as what you say. Even with end-to-end encrypted content, contact lists and metadata can be collected and linked to you.
Social apps are built around identity and contacts, so data linked to you is nearly universal. Tracking and contact upload are the settings worth checking.
A lock answers one question — who can open the app on this iPhone. It does not change what ZERO Messenger sends to its developer; for that, see ZERO Messenger's full privacy report.
What the lock does and does not do
It does
- Ask for Face ID, Touch ID or passcode every time ZERO Messenger opens
- Hide message previews in notifications
- Keep ZERO Messenger's content out of Spotlight and Siri suggestions
- With Hide, remove the icon from the Home Screen
It does not
- Stop someone who knows your passcode
- Encrypt or change how ZERO Messenger stores data
- Sync to your iPad or other devices
- Remove ZERO Messenger from purchase history or Screen Time reports
Don't see Require Face ID?
- Update to iOS 18 or later in Settings › General › Software Update.
- Make sure a passcode is set in Settings › Face ID & Passcode; the lock needs one.
- Some Apple apps (Settings, Calculator, Camera, Maps, Find My, Clock) cannot be locked or hidden.
- If your iPhone is managed by work or school, the option may be restricted.
Other settings worth checking for ZERO Messenger
Contacts
Settings › Privacy & Security › Contacts. Limited Access shares only the people you select instead of your whole address book.
Microphone & camera
Settings › Privacy & Security › Microphone and Camera. The orange and green dots in the status bar show when either is in use.
Notifications
Settings › Notifications › ZERO Messenger › Show Previews: When Unlocked keeps message and account details off the Lock Screen.
ZERO Messenger's full privacy label
The developer states that no data is collected from this app.
Lock these apps too
After you lock ZERO Messenger
Done. You have applied every control the label points to.
FAQ
Does ZERO Messenger have its own passcode?
What happens to ZERO Messenger's notifications when it is locked?
Can someone who knows my passcode open a locked app?
Is a locked ZERO Messenger encrypted?
Why can't I see the Require Face ID option?
Does hiding ZERO Messenger remove it from my purchase history?
Is ZERO Messenger safe? Full privacy report →Does ZERO Messenger track you? →Lock an app: A–Z →All social networking apps →