What does the message “Master key is unlocked” mean?
This notification is shown if you're using the Android version of Threema and have set a passphrase on your master key. In order to prevent the operating system from terminating the Threema process (which would cause the unlocked master key to be lost as it is only held in RAM, necessitating manual re-entry of the passphrase), the app needs to show a notification. This notification has no other purpose and is only required because of the aforementioned limitation of Android.
Please note: in times of extreme memory shortage, Android will even terminate processes that show a persistent notification. In that case, it is possible that you are prompted for the master key passphrase again. This is caused by Android; Threema has no influence on this process termination.
If you experience problems with push notifications, i.e., if incoming messages show up late or only when opening the app (and/or if you are unable to re-establish a connection to the desktop app or the web client), the reason usually lies in restrictions imposed by the device maker.
In such cases, the Threema app doesn’t have permission to be active in the background and/or to transmit data in the background. Please grant the required permissions as follows:
- In Threema, navigate to “Settings > About Threema > Troubleshooting > Fix device configuration problems”
- Select “Disable power restrictions” (if available), and follow the on-screen instructions
- Select “Enable background data” (if available), and follow the on-screen instructions
Should the problem persist after making these adjustments, please follow the device-specific troubleshooting instructions.
Starting with version 4.6, Threema’s Android app requires Android 5.0 or later.
For security and compatibility reasons, it’s required that the Threema apps run on current OS versions. It is therefore inevitable that support for obsolete operating systems is discontinued from time to time.
Users of Android 4.4 can continue to use Threema 4.59 for the time being if the app is already installed. Please note, however, that Threema 4.59 can no longer be downloaded.
Here is an explanation of the most important permissions that Threema for Android requires:
- Read/write contacts
Required for address book synchronization. If the synchronization is off, contact data is not accessed.
Required for contact verification via QR code and for the built-in camera app.
Required for Threema calls and voice messages.
Used for the “Send location” feature.
Used for contact synchronization resp. integration into the account management of Android.
- Modify or delete the contents of your USB storage
Required for reading and storing media files (images, videos, documents).
- Make and manage phone calls
Required to reject incoming phone calls while a Threema call is ongoing.
This problem only affects the Android version of Threema under specific versions of the Android operating system.
Some Android versions (Jelly Bean 4.1.1 is usually affected, and on some Samsung devices even more recent versions) have a bug that affects paid apps. The sync account is lost after rebooting the phone; consequently, the contact synchronization does not work anymore. We're currently searching for a reasonable workaround and recommend all users to update to a newer operating system version if possible.
As a temporary solution, you can turn the synchronization off and on again in the Threema settings. This will cause the account to be recreated and the synchronization will work again until the next phone reboot.
More information on this Android bug can be found here.
You might be experiencing issues with Threema after upgrading your phone's operating system or making other changes to your phone. In such a case it might be necessary to reinstall the app. To avoid a losing your data, please follow the steps below:
- Create a data backup in Threema including media files (find out how).
- Go to Android > Settings > Apps > Threema.
- Tap on “Delete data” and uninstall the app.
- Reboot your phone and reinstall the app.
- Open Threema and restore the previously created backup with our setup wizard.
Did you purchase Threema in the Google Play Store, but can't see updates or an install button in the Google Play Store? Please proceed as follows:
- Make sure you are using the same Google Account as when you purchased Threema.
- On your computer, log into play.google.com. Navigate to Apps > My Apps. Does Threema appear in this list?
- If Threema is listed, delete the data of your Google Play Store and Download Apps on your phone according to these instructions.
- Restart your phone and log in to the Google Play Store. You can now proceed with the update or reinstallation of Threema.
- If Threema is not listed in My Apps, you were using another Google Account when you purchased Threema, or you bought it in our own shop.
Android automatically quits background tasks if you are low on memory space. This might affect a process which is responsible for keeping the passphrase present in memory. You must re-enter your passphrase when starting up Threema. Threema cannot change this.
If you are frequently asked to provide your passphrase, we recommend you to disable it and use global encryption on your device instead. You can find this in your phone's settings: Security > Encrypt phone or Security > Encrypt device.
Save individual (media) files manually
First, tap-and-hold the desired (media) file in the chat. Then, open the menu via the three vertical points and tap on "Save".
Starting with Android 10 and Threema 4.5 for Android, (media) files are saved in the following directories, depending on the file type:
On Android 9 and below, the media files are saved in the directory “Threema/Threema Pictures” (or “Threema Videos”/“Threema Audio,” depending on the file type). Files are saved in the device’s global “Download” directory and can be accessed using the Downloads app.
Automatically save incoming media files
In Threema, navigate to “Settings > Media & Storage,” and activate “Auto-save to gallery.” Automatically saved media files are located in the same directories as manually saved media files, see above.
On Android, distribution lists can be used to send messages to multiple recipients. In contrast to group chats, messages are sent to the recipients separately when using distribution lists. Thus, the recipients are unaware of the fact that other recipients have received the same message. Sending a message to a distribution list is essentially the same as sending the message to each member of the distribution list in a single chat.
To create a distribution list on Android, proceed as follows:
- In Threema’s main screen, open the menu (by tapping the three vertical dots in the upper right corner), and select “New distribution list”
- Select the recipients who shall receive messages sent to this distribution list, and conclude your selection by tapping the check mark in the top right corner
- Specify a name for the distribution list, and confirm by tapping “OK”
If you want to send the same message to multiple recipients without creating a distribution list, proceed as follows:
- Tap “Start chat” in the chat overview
- To select the recipients, long tap on the contacts you want to send the message to
- Tap on the arrow to the right
- Compose and send the message. It will be sent to each recipient separately.
- To go back to the chat overview, tap on the arrow in the upper left corner. Once you’re in the chat overview again, the distribution list you just used is no longer available.
Starting with Android 8.0, apps are required to assign their notifications to so-called “notification channels”. These channels determine which signals (notification sound, light, vibration, etc.) incoming notifications trigger.
For privacy reasons, Threema doesn’t create a separate notification channel for each contact but one for each combination of notification settings. A channel’s ID is a hash of its notification settings.
Editing notification settings
Only edit notification settings for chats and calls in Threema (in Settings > Sound & Notifications or in a chat’s individual notification settings), not in the system preferences. Changes made in the system preferences will be lost.
If you use a Xiaomi device (including Pocophone) running MIUI 10 or later, please enable notification signals as outlined in this guide.
To use custom ringtones and notification sounds on Android, please perform the following steps:
Copy your ringtone sound files to the folder “ringtones” and notification sound files to the folder “notifications”. Alternatively, you can use third-party apps like
Ringtone Maker, which will take care of copying the files to the correct location for you.
- In the Threema app, navigate to Settings > Notifications, where you can now select the sound files you have just added.
In MIUI 11, some notification settings are disabled by default for Threema, and, unfortunately, there’s no way for the app to enable them. However, you can adjust these settings as follows:
- In Threema, navigate to Settings > Sound & Notifications
- Tap on “MIUI settings”
- Enable all (or the desired) notification settings for Threema:
- Show notifications
- Show app icon badges
- Floating notifications
- Lock screen notifications
- Allow sound
- Allow vibration
- Allow using LED light
If an app like Threema creates a notification channel in MIUI 10, only vibration can be enabled as notification signal, all other signals (heads-up, sound, notification light, etc.) are disabled by default and must be enabled manually.
Please enable notification signals as follows:
- In Threema, navigate to Settings > Sound & Notifications
- Select “MIUI Settings”
- Open the first entry in the Chats section
- Enable all settings (Floating Notifications, Lock Screen Notifications, Sound, etc.)
- Return to the previous screen, and repeat the procedure for all other entries in the Chats section
When a new notification channel is added (i.e., when you start using a new combination of notification settings), you will also need to enable that channel’s notification settings as outlined above.
Due to restrictions by Xiaomi, there is no way for Threema to automatically adjust the notification-channel settings for you. For some selected apps, Xiaomi has enabled all notification signals by default. Please get in touch with Xiaomi to learn more.
Starting with version 4.0, there’s a camera built into Threema for Android. To open it, tap the camera icon in the text field. The built-in camera covers basic functionality. You can, however, still use an external camera app if you would like to use special features: Tap on the paperclip icon in the text field, and select “System Camera”.
By default, Threema for Android uses Google’s push service to notify users of incoming messages when the app is in the background. If you prefer not to rely on Google services, Threema Push is available as an alternative. For more information about Threema Push, please refer to this blog post.
Activate Threema Push
To activate Threema Push, navigate to “Threema > Settings > About Threema > Troubleshooting,” and tap “Use Threema Push.” (If no other push service is available, Threema Push will be used automatically.)
Hide persistent notification and icon in status bar
After you have enabled Threema Push, a notification entitled “Threema Push” along with an icon in the status bar will appear. To remove both, disable the “Threema Push” notification channel: Navigate to Android’s notification settings for Threema (e.g., “Settings > Apps > Threema > Notifications”), and turn off “Threema Push.”
In order for Threema Push to fetch new messages in the background, it is required that “power restrictions” are disabled, while “background data” is enabled (cf. dontkillmyapp.com).
At the moment, certain limitations apply for the desktop app and the web client when Threema Push is enabled. Aside from that, the battery consumption might increase slightly when Threema Push is enabled.