Yes, Signal is a free app that users can download and use for free.

Signal uses end-to-end encryption technology to ensure that only the sender and receiver can decrypt the communication content. In addition, Signal does not collect personal information from users, and the source code is publicly available for public review.

Yes, Signal supports group chat. You can create an encrypted group for secure group communication with multiple contacts.

Yes, Signal supports multi-device synchronization. You can use the same Signal account on different devices, and your messages and call history will be synced to all your devices.

Yes, Signal requires an Internet connection to send and receive messages. You can connect to Signal using Wi-Fi or a mobile data network.