- Signal - Signal supports a manual backup and restore option. Basically, messages are not backed up to any cloud storage, and Signal cannot access them. - WhatsApp - WhatsApp can optionally back up the contents of chats to either a Google Account on Android, or iCloud on iPhone, and you have a choice to back up with or without end-to-end encryption. - iMessage - [iMessage] backups… are not end-to-end encrypted by default. This is a loophole we’ve routinely demanded Apple close. - The good news is that with the release of the Advanced Data Protection feature, you can optionally turn on end-to-end encryption for almost everything stored in iCloud, including those backups (unless you’re in the U.K.). - Google Messages - You can optionally back up Google Messages to a Google Account, and as long as you have a passcode or lock screen password, the backup of the text of those conversations is end-to-end encrypted. 


