The Pomera DM100 (Amazon) is a device I’ve used for years. I heard about it when I was about to leave Japan and decided to pick one up. It’s lightweight, portable, and distraction free.
You can create and save files and it even comes with a basic spreadsheet. I think of it as a stripped down Chromebook, that only has the necessary parts for editing and creating documents.
It’s perfect for travel and will give you up to 30 hours of battery life (about the same as a kindle reader).