Problem of Whatsapp filling your phone memory?
Difficult to clean one chat after another?
On Android phone - Whatsapp; To clean ALL of your chats, to clean your phone of all whatsapp chats/images/videos etc., at one shot (while retaining your Groups/Broadcast lists): Open Whatsapp>3dots right top corner>Settings>Chat>Account>Chat >History>Cancel all chats>Select X-Delete media from Phone + Cancel all messages;
ON iPhone: Open Whatsapp>Settings>Chat>Cancel all chats. On iphone: you would have to insert your phone number to confirm the operation!