Ipad Pro and iOS Mail IMAP Folder sync

I have an iPad pro, and using Apple Mail, I assumed that it would allow you to sync all IMAP folders and emails and attachments at once - without opening each folder and each email to do so! Apparently not.

Does anyone know of an app for the ipad/ipad pro that DOES allow full imap syncing?! If that does exist - it will only help apple sell more iOS devices, in my opinion!