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, allows to make end-to-end encrypted voice and video calls, and offers every feature one would expect from a state-of-the-art instant messenger. With Threema Web, 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).
HIGHEST ENCRYPTION STRENGTH 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 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 and video calls • Share videos pictures and locations • Send any type of file (pdf animated gif, mp3, doc, zip, etc.) • Use Threema Web to chat from your Desktop • 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
Dec 1, 2022
Safety starts with understanding how developers collect and share your data. Data privacy and security practices may vary based on your use, region, and age. The developer provided this information and may update it over time.
My wife and I use this exclusively and have peace of mind. She's on iPhone too so it's nice to have all the read receipts and better quality videos that you can't send over text. The one downside that doesn't actually have to do with the app itself, but comes up when using it is that the audio on a phone call starts dropping out when losing service, where a regular phone call would still work just fine. Buy it and force all your family and friends to use it. It's awesome.
96 people found this review helpful
September 10, 2022
Like it but it's very glitchy. Messages sometimes take a while to send but I get the icons so I'm not guessing if it did or not. The video is hit or miss for instances will hang up on occasion. If you receive an incoming call or if you bluetooth disconnects. Love that it has a pin setting and not tie to phone number. Seems very dependable for keeping things secure.
247 people found this review helpful
September 11, 2022
We would be happy to help you to resolve these issues. Please provide as detailed information as possible: firstname.lastname@example.org. Thank you!
August 12, 2020
Can't recommend this enough. The only thing it's missing is self destructing messages, but that's not really as reliable as you might think. You should always be careful of the things you send no matter what and that you full trust the person on the other end. If you care about your security and still want group texts, then Theema is the absolute best messaging app for you. Not having to tie your phone number or email to your account is a huge plus for me, while for some people it's nice to be able to see all of your pre-existing contacts (which you can still totally do if you want) I prefer not to just have people be able to find me like that. I had some of my friends downloaded it (I even paid for some of them to get it, because it's that good) and walked them through skipping adding their phone number and email, had them add a master password (which you have to enter when you turn your phone on; optional) and PIN. You can set the PIN for individual chats. I have one group with 10 people who exchange books with each other. There are polls, now there's video chat to compliment the phone calls, you can transfer your account between phones, there's a web client, the servers are in Switzerland, end-to-end encryption by default, you can verify and add your contacts phones by scanning their QR code to avoid "man in the middle" attacks, and best of all you can just totally ditch your account; delete everything and start over whenever you want with a new anonymous ID. Seriously, I cannot stress it enough, if you genuinely care about security you need to buy this app and get your contacts to but it. Sure you can get Signal, which is tied to your phone number (not to mention gets part of its funding from the State Department and has a broken desktop app that stores everything in plain texts files) or WhatsApp (which is owned by Facebook and probably collects your data to sell you garbage) for free, but your paying for the real thing when you get Threema.
320 people found this review helpful
- New: end-to-end encrypted group calls (audio and video) - New: agree/disagree feature also available in group chats - New: edit received images on the fly and send them right back (tap and hold > pencil icon) - New: send and receive messages with Perfect Forward Secrecy - Security improvements and minor bug fixes