What data is stored in the beta version of Threema 2.0 for desktop, and how is it protected?

Version 2.0 of Threema’s desktop app is a major update that will not only introduce a completely redesigned user interface, but it will also be based on a totally new architecture. Thanks to multi-device functionality, this version of the desktop app no longer requires an active connection to the mobile device.

The beta version of Threema 2.0 for desktop allows iOS users to already use the upcoming multi-device functionality with a mobile device and a computer. iOS users can connect the Threema app for iOS with the beta version of Threema 2.0 installed on one computer and use them independently from each other. (The regular desktop app can still be used alongside the beta version.)

How to Get the Beta Version of Threema 2.0 for Desktop

1. Install and open the beta version of Threema 2.0 for desktop. (There is no browser version available for this beta version.)
2. In the Threema app, navigate to “Settings > Desktop/Web > Linked Device (Beta),” and tap “Add Device.”
3. Follow the instructions on the screen to link your computer to your mobile device.

At the moment, the beta version of Threema 2.0 is only available for iOS, and only one computer can be linked. The development of the multi-device technology for Android devices is underway, and support for multiple linked devices, including tablets, is planned.

The beta version is also available for the business app Threema Work.

To reset the beta version for desktop, please proceed as follows:

macOS

1. Close the Threema Beta desktop app
2. Open the Finder
3. In the Finder, go directly to the following folder: ~/Library/Application Support/ThreemaDesktop (a guide on how to go to a specific folder can be found on this page)
4. Next, delete the folder “consumer-live-default” (or “work-live-default” for Threema Work users)
5. Close the Finder window
6. You can now start Threema Beta again and relink your computer to your mobile device

Windows

1. Close the Threema Beta desktop app
2. Right-click on the Windows icon in the tab bar and click on “Run”
3. Enter “%appdata%” and confirm with “OK”
4. Double-click on the “ThreemaDesktop” folder to show its contents. If there is no such folder, double-click on “Local” and then “Packages,” and open the folder that starts with “ThreemaDesktop”
5. Right-click on the “consumer-live-default” folder and delete it. Please note that this will delete all Threema data stored on this device, including chats
6. Close the window
7. You can now start Threema Beta again and relink your computer to your mobile device

The beta version of Threema 2.0 for desktop (and Threema Work 2.0 for desktop) is beta software that is still being developed. The desktop app is generally stable; however, you may occasionally encounter issues.

These are the current limitations of the beta version of Threema 2.0 for desktop (subject to change):

• The beta version of Threema 2.0 for desktop only works with one iOS device and one computer (Windows/Mac/Linux).
• It’s available for iOS only (Threema for Android is not yet supported).
• The beta version for desktop is only available in English and German.
• It’s required to keep Threema installed on your iOS device. Even though Threema works independently on linked devices, we recommend to open the app on each device at least once a week while connected to the Internet. This ensures new messages are downloaded to both devices.
• New messages sent or received will appear on both devices. Any messages exchanged before linking will not be displayed in the beta version.
• At the moment, videos are sent as file messages. Recording voice messages and sending or receiving polls and locations will be supported in a future release. You can simultaneously use the current desktop app or the web client to circumvent this limitation.
• Status messages and call-related messages are not displayed in the desktop app.
• Contacts and groups are synchronized across devices, but they can only be created and modified on the mobile device.
• It is not yet possible to insert mentions.
• New message notifications may appear on your iOS device even if you have already read the messages in the desktop app. Open the affected chats on the iOS app to mark them as read.
• The “Typing Indicator” and “Do Not Disturb” settings are not yet supported by the desktop app.
• Updates will not be performed automatically. You will be notified when updates are available.
• The chat history stored in the beta version of Threema 2.0 for desktop may not be retained when switching to a future beta or release version of the product. Please keep important messages on your mobile device.
• Enterprise proxies (network-based content filtering) are generally not supported.
• If you have a new iPhone/iPad and move Threema to the new device, Threema 2.0 for desktop will be unlinked and may cause the Threema app to malfunction. To avoid this situation, please remove the linked device on your old iPhone/iPad before switching to the new one (the message history will be deleted in the desktop app). You can then add the device again on the new iPhone/iPad. Alternatively, you can manually reset the desktop app, cf. this FAQ entry.

We are aware of the following technical issues and plan to resolve them with a future update:

• Perfect Forward Secrecy (PFS) is not supported when using the beta version of Threema 2.0 for desktop.
• A chat containing thousands of messages on desktop can result in a slow UI. (As a workaround, you can delete the messages from your computer in the menu at the top right. They won’t be deleted from your mobile device.)
• When deleting a contact on the mobile device, any associated messages and conversations will be deleted on desktop too.