• Thing is, it’s not just Whatsapp. It’s literally every single server-based mechanism to exchange data. You have to trust that the server in question wipes logs on the regular and is not under some secret data collection warrant.

    And ultimately, anything that you can just sign into another device with and retain your messgae history is not fully e2e encrypted…it means a server holds your encryption key for you.

    • The easy test is to see if the service has a password reset option - if so, they can reset the password. If not, you know, only your password or encryption key can unlock it. For example, Signal won’t restore chat history to a new device. So yes Telegram will, but for secret chats no that data is not synced and will be lost.