ntodotxt is great for a task list that is just a txt file and easy to sync.

For calendars I really think hosting your own would be less work in the end.

https://radicale.org/v3.html

Radicale is super small but is a server…

I really wanted this, but couldn’t find anything than worked well. I ended up using tasks.org, an open source todo list that has great calendar functionality and syncing, and moved all my calendar events to it.

merkuro