Some of the questions here are already presented in the section „Questions about WhatsApp“ especially the comparison between the 2 messengers. So please read also there.

Why Threema?

  • Your address book with data of your friends will NOT be copied on foreign servers
  • Your address book with data of your friends and your photos will NOT be sold to someone else
  • Your address book with data of your friends and your photos will NOT be transferred to Facebook
  • Encryption with the most modern technology (not only SSL etc.). Complete end-to-end encryption.
  • You can use Threema even without your addressbook or any other personal data. Identification will be then over anonymously randomly generated Threema-IDs.
  • Threema isn’t tied to a phone number. You can use it even without a SIM card.
  • You can tie Threema with your phone number and/or Email address, in case you want to, as an option. Read more here.
  • Contact lists and groupchats are always only on your phone, not on a Threema server
  • Messages and data will be only forwarded. They will be not saved or copied on a server.
  • Threema is located in Switzerland. Very high privacy rules.
  • Location of servers etc. also in Switzerland.



On which platform can I use Threema?

What does Threema cost?

Depending on the platform between 2,49€/$ und 3,49€/$. This is a one time fee with a life-time licence. Threema in the Google Play Store here, in the Apple Store there.

Does Threema works without a Simcard?

Yes! Threema is not tied to a mobile phone number like other messengers. You can use it with i.e. a tablet and a normal wifi internet connection. This is an advantage, if you want to give your kids a messenger, but no SIMcard.

Is Threema not also synchronising the addressbook?

If you want to: yes. But this is optional. It is your decision and the data will not be sold, if you allow the synchronisation. Nobody forces you to do that (in contrast to WhatsApp). Bute even if you synchronize the addressbook in Threema, , the data will never be copied by threema and will never be sold or used by someone else. Read the terms of use of WhatsApp. They use and sell your data and the data of your friends!

Quote Threema: If you decide to enable the synchronization, email addresses and phone numbers from your address book will only be transmitted to the server in one-way encrypted (“hashed”) form and are additionally protected using TLS encryption. The servers only keep these hashes in volatile memory for a short time to determine the list of matching IDs, and then delete the hashes immediately. At no point are the hashes or the results of the synchronization written to disk.

Manual for making backups

Everbody claims, that he is secure and encrypted…

Yes, but not everybody can proove it 😉

Quote Threema: In August 2015, Threema was subjected to an external security audit. The result confirms that Threema’s concepts fully meet the requirements for secure and trustworthy instant messaging. Furthermore it attests that the implementation of all components relevant for security and privacy was performed properly as specified.

Am I allowed to use Threema according the GDPR after 25.5.2018?

Yes! Threema is in line with all requirements of the new GDPR in contrast to i.e. WhatsApp.

What is the minimum age for using Threema?

According to the new GDPR (as of 25.5.2018) there are 2 answers to this, dependig on how you use Threema.

As long as you use Threema anonymiously and do not synchronise your addressbook, kids are allowed to use Threema, even if they are younger than 16 years old without the approval of their parents.

If you want to synchromize your addressbook with Threema, you need to be at least 16 years old according the GDPR or you need the approval of your parents.

Attention: Even if you synchronize your addressbook in Threema, it is all still in line with the law and the GDPR, because the data of your friends are not copied and/or sold by Threema to someone else. This is a major difference to WhatsApp and many other messengers!

Regarding the addressbook/ forward private data of my friends: Where is the difference to WhatsApp?

Threema gets the addressbook encrypted. It can not read or access the data. Threema does not save the data on its servers. After the successfull synchronisation (within milliseconds), it deletes them immediately. Threema will at no point give these data to a third party or keeps them on their own server. No data will be sold. This is why Threema is fullfilling 100% the requirements of the new GDPR.

WhatsApp forces you to copy your addressbook to their servers. Otherwisse you can not use WhatsApp. This is mandatory. If you do so, you agree according to their terms of rules, that they can do basically everything with the data. No matter whether it is your data or the data of your friends in your addressbook.

Even worse: By accepting the terms of use of WhatsApp, you confirm, that you have the written approval of ALL your friends saved in your addressbook, that they sent you a writte approval and agree that you give WhatsApp their private data. No matter whether they use WhsstApp themselves or not. So legally, you are now responsible for this and everybody can sue you, if you can not show this written approval of all your friends.

Since nobody has these written approvals (do you?), it is against the GDPR. In Germany this was already the case in some lawsuits with big fines for WhatsApp users.

I changed my mobile number

With Threema this does not matter. As long as you use the same smartphone, nothing changes. No action needed.  The Threema Licence is for a device, not for a phone number.  It is hardware-dependant. If you change your device, simply make a backup of your Theema ID beforehand and import that backup after switching the smartphone. Read here on how to do this.

I know some of my friends have threema, but I do not find them in my threema contacts

Did you synchronize your contacts already? Move with your finger from top to buttom. More information here.

Your friends need to tie their Threema ID with either their mobilde phone number or with their Email address, that you have stored in your addressbook. Otherwise they are anonymous (for you invisible) and they need to give you then their Threema ID directly.

Why Threema instead of WhatsApp?

Threema offers everything what WhatsApp can give you. You will not miss anything. But you you do not sell the data of your friends with Threema.

I do not talk about encryption. I do talk about the business model of WhatsApp. They make money with selling the data to others.

Threema earns money by selling their licence to you. This is fair and transparent. Threema does not save data on their servers. It is all yours.

All data stay on your local phone/device.


But a lot more people have WhatsApp…?

That is the most popular counterargument. 🙂

Who is everybody? With whom do you really communicate over WhatsApp? With WhatsApp users in China or India?

According to this, you should even not use WhatsApp. Because a lot more people have Email than WhatsApp 🙂

Seriously, how many friends do you have? With whom do you communicate? With WhatsApp users on the northpole? or in Nowosibirsk?

Stay realistic. Everyone has a limited circle of friends with whom you do communicate. Let’s assume you have 50 friends (which is already a very high number). This looks already a lot smaller than „millions of WhatsApp users“, right?

Now you realize, that is actually up to you to change something, if you really want it. Yes, you can! No lame excuses anymore 😉

What are the disadvantages of Threema?

  • You need to sync your addressbook yourself. With the finger from top to buttom. See here
  • If you plan to get a new phone, you need to make a Threema backup beforehand to keep your lifetime licence and all old chats.  See here.
  • Currently there are less Threema users than WhatsApp users. In real life this is irrelevant. See argumentation above.

Why Threema and not other alternatives?

There are many alternatives to WhatsApp. Not only Threema. See here.

Except for Signal, there is simply no other messenger with data and privacy protection like Threema.


How to install Threema and how to set it up ?

Video in German:

Video (German): How does Threema works compared to WhatsApp?