When one of your contacts subscribes to Signal, you will see a message saying that the person has joined Signal. Now you know you can contact him through the app. If you do not want to see these notifications, you can turn them off.
How to turn off your Signal Contacts notifications
When a phone number from your contacts is registered in Signal, you will see a notification informing you that you can contact with him through the application. The name associated with this person comes from the contact information stored in phone you.
To hide these notifications, open the app on your iPhone or Android phone. Touch your profile picture or username initials in the upper left corner of Signal chat list.
Click "Notifications" in the application settings.
You are ready - From now on Signal will not notify you when friends, family members, co-workers or other contacts become members. In the application it will look natural. If you click on the "New Message" icon, you will see all your contacts on Signal, ready for communication.
Can you prevent Signal from telling others that you are already involved in the application?
There is no way to prevent Signal from informing people when you join the app. If someone has your phone number on contacts The application will notify you that your phone number has been registered. This has nothing to do with whether you allow the application to access your own contacts.
The only way to avoid this is to use a second phone number. The Signal is designed to work with phone numbers to be an easy replacement SMS, that's why it works like this. If you want a chat service that does not use phone numbers as IDs - for example, if you prefer usernames that do not expose number of your phone - this is not the right application for you.