Threema. The Secure Messenger

Threema. The Secure Messenger

By Threema GmbH

  • Category: Social Networking
  • Release Date: 2012-12-28
  • Current Version: 5.6.2
  • Adult Rating: 4+
  • File Size: 74.99 MB
  • Developer: Threema GmbH
  • Compatibility: Requires iOS 15.0 or later.
Score: 4.2252
From 373 Ratings


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 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:



  • Almost perfect.

    By surfboy11
    The only thing missing is automated ephemeral messaging. I see the manual option, but would prefer to set a timer and have it done automatically as some other apps do. Any chance this is on the roadmap?
  • Not able to make calls after update

    By MomoE2E
    After updating, the app is no longer functioning for phone calls in China. I'm uncertain whether this is due to government restrictions or if the app has encountered bugs.
  • Too many BUGS 🐞

    By Carlosx33
    It’s good in general but lately many bugs running around and after the latest IOS update no sound for incoming messages. Plz fix it and remove the bugs , I’m just waiting for an update for threema !
  • Keeps freezing

    By Russ pound
    I use this app everyday and I like it, but it freezes alot. It’s been happening for months now on my IPhone. It used to freeze the moment I’d send a text or a picture through the app, but lately it even happens while I’m typing. It won’t look frozen; the text cursor will still be flashing like I’m able to type more but I can’t do anything. I have to swipe from the bottom and close out of the app, and then open it again. Happens about 5 times a day. This doesn’t happen to any other apps on my phone.
  • Calls disconnect regularly

    By SonyReaderSucks
    The call function is still very buggy. To date, I have been unable to complete more than a 15-30 second call without the app disconnecting. It also takes up to 2 minutes at spook up to ‘initialize’. If the security is a robust ad claimed, perhaps the calling and video technology will catch up? As a paid app, albeit no,I al, the ‘freebies’ are still much better. Help!
  • Was Better before all the updates

    By Zombie slayers
    Re review here… I understand you need to update apps to keep them relevant. I’ve had this app for years, but I will say all these new updates are making it far more complicated and far harder to navigate than it needs to be. It also is taking far more time to load with every new update. So, In my opinion, which means nothing, I think it was better before all these latest updates.
  • Mobile app good, desktop meh

    By RaditudeForever
    I wish the desktop app didn’t require the iPhone to be open and in the Threema app just to use it. Major strain on my battery. Signal and Session don’t require that. Mac Desktop app also needs dark mode like yesterday. Update 2023/09/06: Thanks for the info about the beta. That addresses my issues, and I’ve updated my rating to 5 stars.
  • Great app

    By xsoldier777
    This app is awesome. Like seriously thank you to whoever made it I think I have been using it for two years. Good job to whoever made it.
  • It’s full of bugs - can I trust the privacy?

    By Rainy Goodness
    If the user experience is any indication of what’s going on behind the scenes, then it’s hard to trust this app. Calls routinely drop with no explanation, the app randomly scrolls to much earlier dates while the scroll to latest button doesn’t function. Generally, you don’t get the feeling you’re using something solidly built. It feels more like a prototype, which for me, casts doubt on the privacy features themselves. I wish they’d focus on the UX a bit more and make it friendlier and more polished.
  • Best Secure Messaging App!!

    By scott4weaver
    I love great security! I love Threema’s commitment to a very secure experience! My only bummer is that here in the USA, I rarely run in to anyone that has heard of Threema and even fewer who use it. Most everyone I know of uses Apple Messages and are so committed to that service.