I want to sync calendars across 2 Android devices. I don't want to use Google servers.
Is there any Android or Windows software that will support syncing calendars across multiple Android devices?
I would prefer something that will not require an always-running server, as I just need to sync on-demand. But that's not a hard requirement.
Gratis is always good, but I will consider options with a 1-time payment up to 50 euros/dollars, or an annual payment up to 10 euros/dollars.