WhatsApp is now rolling out an 'undo' feature to recover messages deleted by you.
The feature has been rolled out to some of the users on iOS beta.
Take a look at this screenshot by WABetaInfo to understand how the feature works.
The 'Undo' feature won't remain available forever after you delete the message.
Nor just this, group admins of WhatsApp groups will now get the option to delete any problematic or inappropriate messages by members in the group.
It is still unclear when the feature will be available to everyone.