As per reports that have come out WhatsApp is bringing end-to-end encryption to WhatsApp chat backups for iOS. It was known that WhatsApp was developing this feature for some time now and finally it is being released on WhatsApp beta for iOS. According to a report by WABetaInfo, the end-to-end encryption for chat backups will be releasing today for specific iOS beta testers for WhatsApp Messenger as well as Business beta. If you are a beta tester you can check for the availability of this update by going to WhatsApp Settings>Chats>Chat Backup> End-to-end Encrypted Backup.
Another thing to be kept in mind is when you are using WhatsApp encrypted chat backup you must make sure that the backup for the WhatsApp app is turned off. This should be done otherwise the chats backed up on your iPhone will not be encrypted. For this go to Settings>Your Name>iCloud>Manage Storage>Backup>Disable WhatsApp.
The next important point is that when you are using encrypted chat backups you need to remember the password to decrypt your chat backups. A password has to be chosen that will be used to encrypt future backups. This password will be required to restore a backup.
Just some time back the encrypted chat backups for Android beta users had been rolled out by WhatsApp. Now that it’s available for iOS beta users too, it can be expected that it will be rolled out to all the users soon.