RocketBook Notepad and App. I use the A4 version of this as my main notebook. The ability to be able to erase mistakes easily with a Pilot Frixion pen or wipe a whole page with a wet cloth, make this my reusable notebook of choice.
Using the app, I can quickly scan a page and it automatically uploads to most cloud based services like iCloud, Evernote, OneDrive and many more.
Great for business meetings and the environment!