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How to Lock Threema. The Secure Messenger on iPhone

iOS 18 Face ID lock and Hidden folder · Threema GmbH · checked November 2026

Time needed
4 taps
Needs iOS 18 or later

Works for Threema. The Secure Messenger whether or not it has its own passcode. No download needed.

Short answer

Touch and hold Threema. The Secure Messenger's icon, tap Require Face ID, then confirm. On iOS 18 and later that puts Threema. The Secure 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 Threema. The Secure Messenger with Face ID

  1. Find Threema. The Secure Messenger on your Home Screen or in App Library.
  2. Touch and hold the icon until the quick-actions menu opens.
  3. Tap Require Face ID (or Require Touch ID / Require Passcode, depending on your iPhone).
  4. Tap Require Face ID again to confirm. Threema. The Secure Messenger now asks for authentication every time it opens.

To test it, close Threema. The Secure Messenger from the App Switcher and open it again. You should see the Face ID prompt before any content appears.

Hide Threema. The Secure Messenger in App Library

  1. Touch and hold Threema. The Secure Messenger's icon and tap Require Face ID.
  2. Choose Hide and Require Face ID instead of Require Face ID.
  3. Confirm. The icon leaves your Home Screen and moves to the Hidden folder at the bottom of App Library.
  4. 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 Threema. The Secure Messenger?

Threema. The Secure 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 Threema. The Secure Messenger sends to its developer; for that, see Threema. The Secure 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 Threema. The Secure Messenger opens
  • Hide message previews in notifications
  • Keep Threema. The Secure 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 Threema. The Secure Messenger stores data
  • Sync to your iPad or other devices
  • Remove Threema. The Secure 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 Threema. The Secure Messenger

  1. Tracking

    Settings › Privacy & Security › Tracking. If “Allow Apps to Request to Track” is off, apps cannot ask, and they are told to treat you as having declined. You can also turn it off for this app alone.

  2. Contacts

    Settings › Privacy & Security › Contacts. Limited Access shares only the people you select instead of your whole address book.

  3. Microphone & camera

    Settings › Privacy & Security › Microphone and Camera. The orange and green dots in the status bar show when either is in use.

  4. Sign-in

    When creating an account, Sign in with Apple can give the app a relay address from Hide My Email instead of your real one.

  5. Notifications

    Settings › Notifications › Threema. The Secure Messenger › Show Previews: When Unlocked keeps message and account details off the Lock Screen.

Threema. The Secure Messenger's full privacy label

App Privacy label Developer-reported · checked November 1, 2026
Used to track you
0types

None declared

Linked to you
2types
Not linked to you
1type

Is Threema. The Secure Messenger safe? Every data type explained →

Lock these apps too

After you lock Threema. The Secure Messenger

Tick what you have done
Tick each step as you do it on your iPhone.

Done. You have applied every control the label points to.

FAQ

Does Threema. The Secure Messenger have its own passcode?
Some apps offer an in-app PIN or biometric lock in their settings. The App Store privacy label does not say whether Threema. The Secure Messenger does; the iOS 18 lock works regardless.
What happens to Threema. The Secure Messenger's notifications when it is locked?
Locked and hidden apps do not show message previews or content in notifications, and their content does not appear in Spotlight search or Siri suggestions.
Can someone who knows my passcode open a locked app?
Yes. If Face ID fails, the lock falls back to your device passcode. Keep the passcode private if the lock matters to you.
Is a locked Threema. The Secure Messenger encrypted?
The lock controls who can open the app on this iPhone. It does not change how the app stores or syncs data. Encryption depends on the developer and on your device passcode.
Why can't I see the Require Face ID option?
You need iOS 18 or later. Some Apple apps such as Settings, Calculator, Maps and Camera cannot be locked or hidden.
Does hiding Threema. The Secure Messenger remove it from my purchase history?
No. Hidden apps still appear in App Store purchases and in Settings › Apps, and Screen Time reports still include them.

Is Threema. The Secure Messenger safe? Full privacy report →Does Threema. The Secure Messenger track you? →Lock an app: A–Z →All social networking apps →

Facts on this page come from Apple: lock or hide an app on iPhone, as reported by the developer. Checked November 2026. How we collect data · Report a correction