Conventional chat services identify their users by means of the users’ phone numbers. Since a phone number points to the identity of its owner, it’s not possible to use such services anonymously. But how is that a drawback? Why should you care about anonymity if you only communicate with friends you know personally?
In order to address these questions, it’s necessary distinguish two kinds of anonymity:
- Anonymity in regard to the chat partner – “horizontal anonymity”
- Anonymity in regard to the chat service – “vertical anonymity”
Threema accommodates both types of anonymity:
- Instead of a phone number, the Threema ID serves as unique identifier. Since this ID is a random sequence of characters, it doesn’t reveal any details about the owner’s identity. Therefore, it’s possible to contact someone via Threema without disclosing one’s identity to the contacted person.
- Linking personally identifiable information (such as the phone number or an email address) to one’s Threema ID is optional. Therefore, Threema as service provider has no way of knowing a user’s identity if they don’t link a phone number or email address to their ID.
Horizontal anonymity enables you to communicate with like-minded people in group chats without having to expose your identity in the process. Due to the rise of censorship in social media, this use case is becoming increasingly popular. Another typical scenario is the use of Threema as a whistleblowing channel, and there are even churches that use Threema as a “digital confessional”.
While anonymity in regard to the chat partner may not be of equal importance to all Threema users, vertical anonymity is relevant to all users in the sense that each of them chooses whether to use this privacy feature or not.
By disclosing your identity to every Internet service you use, a comprehensive record of your online activities can be compiled by combining the user data from the different sources. If, however, you remain anonymous to a service, you can be absolutely sure that the respective data will not be merged with your user data from other sources and therefore can’t be misused for advertising or other purposes.
If you decide to link your Threema ID to your phone number or email address (in order for your contacts to easily retrieve your ID), this data is safely stored on the Threema server in encrypted form. However, if you don’t disclose any personally identifiable information in the first place, your anonymity is guaranteed, and your privacy is protected in the best possible way. Because as long as someone’s identity is unknown, their privacy can’t be violated; that’s why anonymity is the ultimate privacy protection. In short, anonymity is to privacy what end-to-end encryption is to security.