Safest Messenger App – Threema

Keys Kept On Device - High Security

Threema creates and keeps the keys for the encryption on device. They can’t be passed to another device which means if you have multiple devices you need to have a workaround to see messages on all devices at the same time. It isn’t difficult to set this up. You’ll need to work with multiple IDs. Even if you have three devices, for example my wife has two iPads and iPhone. Each of these devices have a different Threema ID. You have your first ID which is connected to an email address and/or a telephone number. Or not, you can go completely anonymous if you wish. Your contacts will have to find you with the ID code from Threema rather than your email address or phone number.

  1. On your second device you create a second ID.
  2. Don’t link this new ID with your email address or your phone number. Give it a nickname which includes your name and the name of the device. Your contacts will recognise the name and you will recognise the name of the device.
  3. Still on the second device, perhaps your iPad, scan the QR code on the iPhone where your first ID is residing. You can save that contact as “My iPhone”.
  4. Then use your iPhone to scan the QR code for the second ID on your iPad and save the contact as “My iPad”.
  5. Still on your iPhone create a group with the contact “My iPad” included as well as the contact you are connecting with.
  6. When your contact sends a message to the group chat it will go to both your iPhone and iPad.
    Your group chats are end-to-end encrypted in the same way as our single chats. This will work just fine and you shouldn’t have any difficulties. The only problem could come if someone does a data backup and their group chat could be different from everybody else’s. If this happens the group administrator can do a synchronisation to set things right again.

Threema Secure Message app

Other cool things with Threema

If you need to ask a question of several people rather than doing a back-and-forth between everybody when it use a poll. Just set up your question and the possible answers. All the recipients can vote. When all the votes are in you can close the poll and see the results. Everyone who voted can see who voted for what. There is also a ‘Agree or Disagree’ feature, which is basically a thumbs up or thumbs down.
Threema Poll

Fantastic Encryption Features

The encryption features are completely and fully end to end. There’s no way a man in the middle can successfully hack you. It is not possible for any messages whether they be single chats, group messages or files to be sent unencrypted. You can’t accidentally send something without encryption. The key pair generation is kept completely within the device and the private key is kept secure. It’s also technically impossible for Threema to decrypt any user’s messages.

The man in the middle attack is prevented by verification of identities – Threema ID. I can scan a contact’s QR Code when we are face-to-face in the same room. Or I could ask my friend to send me a picture of the QR Code by other means. That could even be by snail mail or any other trusted means of communication. If someone was going to try and pretend to be my contact I can test identity using verification in Threema.
The Threema ID identification code which is eight letters long I can use to add someone to my contacts.

Threema Profile

Get the Settings Right in Threema

  • If you don’t want to send the indicator you are typing, you can switch that off.
  • Easy to block unknown people so you stop spam in its tracks.

  • Exclude people if you need to. Good having control over who can send you messages.
  • Do you want to let people know the message they sent to you has been read? If not, turn off the read receipts.
  • In the settings decide if you want to allow audio calls.
Threema Settings

Buy the Book

One way of staying safe is to avoid using email. Sending email is the equivalent of putting your private data onto a postcard. The postcard (email) can be read easily as it passes through the postal system. Your information is naked and without protection. There are illicit sniffer applications which look at email as it goes through servers. Similar to the Google email system which looks to see what adverts it should put in front of you. That’s why you get a free service from Google. You are the product being sold to the advertisers.

Test Threema by sending me a message
In the Book you will find my Threema ID and QR Code

Ask me whatever about security and privacy and I’ll do my best to answer the questions. Try out message apps, OpenPGP or other encryption techniques,

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