1. configure your feeds (RSS/Atom, but also Twitter/Reddit) in a simple dashboard 2. connect Google Drive (Dropbox/OneDrive to be supported eventually) 3. on a daily schedule, a pdf file with your feeds' content will be sent to your GDrive account, which can be synced on your tablet device.
If interested, I've got a survey you can fill out to get alpha access: https://forms.gle/qmy6WMgHLxWiEgx4A
It basically reads a list of feed URLs, with categories, loads and parses them and writes out a simple HTML page with the headlines. Saves me a lot of trouble - just run it on a web server and publish the created HTML files in a directory.
Though I'm running into a stubborn issue where FreshRSS doesn't parse the date correctly... so your mileage may vary.