I am also using it on mobile (syncing my vault from laptop->NAS<-cell phone). Works quite well, but I can not say mich about performance, as my cell phone is having problems in general at the moment.
However, it feels really smooth after initially loading the app and I have no problems to report.
It fits well for me. I set up multiple queries in my daily note template to catch tasks that are due today or I wanted to work on today, for long-term tasks and for overdue tasks. You can group tasks by adding tags which I use often. You can add a new task anywhere in your notes and it will show up in the query. So I put tasks in all notes that I am working on and will be reminded of them in my daily note. It is often updated with new features, just try it out and see if it works for you. I can not complain and only recommend it.
Main plugins for me are dataview and tasks. Add the mininal theme and style settings and that is it. Although I enjoy browsing Obsidian roundup to see what is new in the world of plugins.
Just a quick note for the Privacy Policy, Data Processing Agreement and Cookie Policy: this EU law (GDPR) and is mandatory for all EU states. So its not specific to Germany.