Thanks for the informative and helpful list of tools.

* I also used CherryTree for quite some time – till I discovered Zim (https://zim-wiki.org) and never looked back. Extremely user friendly and based only on text files which makes it possible to sync without problems and edit even with no Zim installation available. On Android there is Markor (https://gsantner.net/page/projects.html#markor) that offers syntax highlighting.

* As more and more people are getting aware of Google’s activities beyond data collection, like massive censorship, it’s a very good idea to avoid them as much as possible. Instead of Google calendar, I used extensively, I found that Nextcloud calendar is covering everything I need, i.e. notifications via email and pop-up, syncing between Linux and Android devices. On that note, a Nextcloud account can also be used to manage contacts, bookmarks and much more.