Threema. The Secure Messenger

Threema GmbH

About this app

Threema is the world’s best-selling secure messenger and keeps your data out of the hands of hackers, corporations, and governments. The service can be used completely anonymously. Threema is open source and offers every feature one would expect from a state-of-the-art instant messenger. The app also allows you to make end-to-end encrypted voice, video, and group calls. Using the desktop app and the web client, you can also use Threema from your desktop.

PRIVACY AND ANONYMITY
Threema is designed from the ground up to generate as little data on servers as possible. Group memberships and contact lists are managed on your device only and never stored on our servers. Messages are immediately deleted after they have been delivered. Local files are stored encrypted on your mobile phone or tablet. All this effectively prevents the collection and misuse of your personal information, including metadata. Threema is fully compliant with the European privacy legislation (GDPR).

ROCK-SOLID ENCRYPTION
Threema end-to-end encrypts all your communication, including messages, voice and video calls, group chats, files, and even status messages. Only the intended recipient, and nobody else, can read your messages. Threema uses the trusted open source NaCl cryptography library for encryption. The encryption keys are generated and safely stored on the users’ devices to prevent backdoor access or copies.

COMPREHENSIVE FEATURES
Threema is not only an encrypted and private messenger but also versatile and feature-rich.

• Write text and send voice messages
• Make voice, video and group calls
• Share videos pictures and locations
• Send any type of file (pdf animated gif, mp3, doc, zip, etc.)
• Use the desktop app or the web client to chat from your computer
• Create groups
• Conduct polls with the poll feature
• Choose between a dark and a light theme
• Quickly and silently reply with the unique agree/disagree feature
• Verify the identity of a contact by scanning their personal QR code
• Use Threema as anonymous instant messaging tool
• Synchronize your contacts (optional)

SERVERS IN SWITZERLAND
All our servers are located in Switzerland, and we develop our software in-house.

FULL ANONYMITY
Each Threema user receives a random Threema ID for identification. A phone number or email address is not required to use Threema. This unique feature allows you to use Threema completely anonymously – no need to give up private information or to open an account.

OPEN SOURCE AND AUDITS
The source code of the Threema app is open for everyone to review. On top of that, renowned experts are regularly commissioned to conduct systematic security audits of Threema’s code.

NO ADS, NO TRACKERS
Threema is not financed by advertising and does not collect user data.

SUPPORT / CONTACT
For questions or problems please consult our FAQs: https://threema.ch/en/faq

Ratings and reviews

Good messenger but still odd behavior. Every time I open the messenger it refreshes the app (fades out and re open the app) annoying because you have to wait a few seconds until to write or started messages are gone. Edit: Seems better now, possible android core issue.

At one point, the app began to crash and not open consistently. After some exchanges with threema support, I was asked to enroll in an internal beta to send logs of how the app would function. The issues were resolved and threema support was very responsive and helpful. This is a good example of how paying for something has benefits. I would highly recommend this app to anyone, not just for privacy and security, but for their support as well.

Amazing app. A must have. O ly thing that would make it better is if I could use a SECO DARY password and enter it right into my log in fields. A seco dary passqord buy when i click LOG IN. IT WILLL AUTODELETE EVERYTHING. I wish I could create a secondary password. So even if a cop is watching you, he can say put your oassword in. You put your password in, it logs you in. But if you put your secondary password in he won't know. So he thinks you're logging in but your secondary pw is auto delete.

What's new

- Added a highlighter pen function to image editor
- Support for animated WebP images
- Numerous optimizations and bug fixes