I find it helpful in those situations to remember what David Allen said about when that happens: "you may have fallen off the horse, but you can always saddle up again"
Focuwriter is great. Especially if you just want to write on a blank canvas without distractions. Great for long form, write from the head. My next favourite is Marktext, which I use more for manuals and such in non fullscreen mode. Obsidian for notes and lots of referential info. Qownnotes for snippets related to computing. Logseq for work related notes. If I would still have a Mac, add NValt based on notational velocity.
Just use fdroid. It's a nice app, great for hiking. Last time I used it (2 years ago), it seemed to be quite a battery drain, not sure they fixed it in the meantime.
That it is a walking/boating city is exactly what is so great about it. It's a great place to simply walk and get lost in the smaller streets until you find a grand canal. It surely has grown on me.