Hosting fees for synchronization service until 2028
199% of €120 goal
Feeder works entirely offline but to make it easier for people with multiple devices there is a hosted service for synchronizing the read status between devices.
Hosting this costs between 10 and 15 euros per month.
I'm a developer maintaining a couple of free software projects. Most notably Feeder, which is IMO the best RSS-reader for Android out there.