Important Features That Help Protect Privacy on Zalo

Vietnam has over 74 million users using the messaging app Zalo. In a relative comparison, the population of Vietnam is 99.46 million people (as of December 2022). Therefore, the estimated number of users on this messaging platform accounts for over 74%.

End-to-End Encryption (E2EE) on Zalo

End-to-End Encryption (E2EE) is a method of encryption that ensures only the sender and recipient can read the sent messages. With this encryption method, even if the message stream is intentionally attacked, hackers cannot access the content sent by users.

Through E2EE, all types of Zalo messages (text, images, videos, files, etc.) are encrypted into random character strings that are meaningless and can only be decrypted directly on the recipient’s device.

This feature is built and developed by Zalo based on the open-source Signal Protocol. The Signal Protocol is an internationally recognized protocol widely used by leading messaging applications worldwide for E2EE. Many reputable global technology experts have tested and endorsed the quality and security of the Signal Protocol over the years.

With E2EE, only the devices of the sender and recipient can read the message content. When a user sends a message, the content is immediately encrypted into characters (e.g., AxZ/Hn8DEV-u10dskYoatTK=VD). This encrypted code remains unchanged throughout the transmission process and is only decrypted back into the original content when it reaches the recipient’s device. This feature is currently applied to personal messages only. For group chats, Zalo is testing and gradually expanding the feature soon.

To enable the encrypted chat feature on Zalo, users simply need to go to the “Settings” section in the app and choose to upgrade to “End-to-End Encryption.” Currently, E2EE can be used on both the mobile and desktop versions of Zalo.

Account Security

To ensure the best account security, users should regularly check the application through the following features:

Device management: Allows users to view login history and support logging out from secondary or untrusted devices. To use this feature, users should go to the “Account Protection” section and check the information.

Two-factor authentication: Helps users enhance account security by requiring mobile device confirmation whenever logging in from a new computer.

Zalo app lock: Requires entering a code every time the app is opened.

Self-destructing Messages

Self-destructing messages on Zalo are one of the privacy protection methods favored by users. With this feature, users can actively protect the privacy of important conversations by setting messages to self-destruct after 1, 7, or 30 days according to their personal preferences. After enabling this feature, a countdown clock will appear beneath each message in the conversation, reminding users of the importance of the exchanged information.

Self-destructing messages will be permanently deleted and cannot be recovered even if the feature is turned off. This feature is available on both mobile and computer versions of Zalo.

Leaving Groups without Disturbing Other Members

This feature allows users to leave chat groups on Zalo without notifying other members. By enabling the option to leave groups and simultaneously blocking others from inviting you back, strangers will not be able to directly add you to groups. Instead, they will have to send an invitation and wait for your acceptance.

The feature of blocking strangers from adding you to groups is favored and frequently used by many users as well. This is a common situation encountered when using messaging applications.