General

What does the name “Threema” stand for?

What makes Threema special?

What is a Threema ID?

On which operating systems and devices can I use Threema?

Is Threema available in my language?

Is Threema suitable for business use?

Features

What features does Threema offer?

How do I create a poll?

How do I use the agree/disagree feature?

What are Private Chats and how can I use them?

How do I add text formatting to a message?

What is the QR code good for?

Can I use Threema without a SIM card?

How can I export a chat?

How can I send a file?

How can I change the design theme?

How do I quote a text message?

Security and Privacy

What makes Threema secure?

How does Threema compare to other messengers with encryption?

What’s special about Threema’s privacy protection?

Which data gets stored at Threema?

Are messages encrypted when they are stored on my device?

Could you decrypt my messages, for example if you were required to by law enforcement?

How do you protect yourself against man-in-the-middle (MITM) attacks with Threema?

Will my address book data be sent to your servers?

Where are the servers located?

How does Threema audit its code?

How and where is my key pair generated?

Purchase

How can I give Threema away?

How can I purchase and distribute multiple Threema licenses?

How can I reinstall Threema without paying again?

Can I move the purchased app between operating systems?

How can I install or update Threema from the Threema-Shop?

Is there anything to consider if I buy Threema from Amazon appstore?

Where can I buy Threema, and how can I get the latest version?

Can I install Threema on multiple devices?

Is there an age restriction for Threema?

ID and Data Backup

Why is it important to backup my ID?

How can I move my ID to a new device?

I got a new phone – how do I transfer my data?

What is the difference between a Threema ID and an ID backup?

I lost my data! Can Threema somehow recover and send it to me?

I didn't receive my verification email or SMS! What can I do?

I have a new ID — How can I delete my old ID?

I got a new phone number — what do I do?

I created a new ID — how come my contacts still see my old ID?

Sending / Receiving

What do the symbols next to a message mean?

Why do messages to certain contacts not appear as read or delivered?

What does the colored stripe or the colored dot in the title bar mean?

Why are incoming messages sometimes delayed or only arrive once I open the app?

How can I send emoji?

Why don't previews in push notifications work properly?

Why doesn't my chat partner receive my messages?

How can I make sure this is working when I don't know anybody who has installed it yet?

What kind of data is transmitted via Google Cloud Messaging (GCM)?

How long do messages stay in queue for delivery?

I am receiving unwanted messages. What can I do?

Why can't I send a video?

How can I mute individual chats?

What does it cost to send a message?

Group Chats

Is there a group chat feature?

How can I leave or delete a group?

Can members be added to/deleted from an existing group?

Trouble with group chats — What can I do?

Why are my groups missing after restoring an ID backup?

Contacts

What do the three colored dots next to a contact mean?

Why are some of my friends missing on my Threema contact list?

Why are some contacts grayed out?

Some of my contacts are displayed twice in my address book — what can I do?

How can I assign a photo to a contact?

How can I change/set the name of a contact?

How can I retain my contacts' verification levels?

What is the Threema Channel?

What’s the purpose of the “ECHOECHO” ID?

Android

Why am I not receiving any push notifications or experiencing delays?

Which Android version is required?

Which permissions are used under Android, and for what purpose?

Can I buy/use Threema without a Google Account?

Why does the synchronization not work anymore after rebooting my phone?

How can I reinstall the app without any loss of data?

Trouble with the Google Play Store — what can I do?

Why do I keep getting asked for the Passphrase of the Master Key?

What does the message “Master key is unlocked” mean?

Where do I find the master key lock button?

How do I save received media (photos/videos/audios)?

iOS

How can I give Threema permission to access my photos?

Why am I not receiving any push notifications or experiencing delays?

How can I share files using Threema on iOS?

Which iOS versions are supported?

Windows Phone

How can I create a group chat on Windows Phone?

Why am I not receiving any push notifications or experiencing delays?

Threema Web

What is Threema Web?

How do I use Threema Web?

What are the system requirements for Threema Web?

What features does Threema Web offer?

What is a session and what is the purpose of the session password?

What’s special about Threema Web?

How does Threema Web work?

In which languages is Threema Web available?

Why does establishing a connection to Threema Web fail?

Why are sessions not being saved?

How can I enable desktop notifications for Threema Web?

Miscellaneous

Can I use Threema on a BlackBerry 10 device?

Which URL actions are supported?

I have received an SMS with a code – where do I enter it?

I forgot my PIN/passphrase/lock code. What can I do now?

What is Threema Gateway?

How can I delete chats and media files?

Where can I find Threema’s source code?

What is Threema Work?

How can I invite friends to join Threema?