I've tried lot of different apps, but I think I've settled on Trilium for now.

It doesn't have a great mobile experience, but the web app works fine on mobile. The app in general is super customizable and way easier to write scripts / plugins for.

Logseq but I know the sync is tricky

I'm using Notion for everything now. I heavily rely on reminders scattered everywhere because Todo lists don't work for me.

Notally on Android. Simple and light weight. Has widget support too.

Hedgedoc and Nextcloud Notes

I use the one that comes with my iPhone. No problems with it…

I'm using trilium and very happy with it.

Logseq

Siyuan. Ive been using it for a while now and find it very effective for my needs. Its gone through quite a few updates since i started using it and became open source in that time. It even has an android version as well which i do have installed on my phone but admittingly rarely use. I prefer writing information on a keyboard generally.

I used to use Joplin, I liked that it integrated with my Nextcloud, and the markdown format. However, the way that it handles the markdown files was too black-boxey to me, with the way it split them up in a weird scheme.

Now I use Ghostwriter with straight markdown files inside my Nextcloud folder. So I still get the syncing functionality, but a more flexible setup that doesn't require a specific app to access all of my notes.

I still use Keep. That have yet to fuck it up, but I'm sure they will eventually. Just like every god damn thing they do.

Markor + synvthing

Joplin uses it's own database so interoperability is not perfect. Markor is so effing cool. That's on Android. On the laptop I use want ever is best suited for the task. Most often, a vim variant of notepad++

https://github.com/gsantner/markor

Emacs+org-mode

OneNote was my favorite until it started crashing on my iPad every 3 minutes.

I use https://simplenote.com/ I was thinking about switching to a Foss alternative from fdroid but haven't yet. Works good for me.

I've been using Trilium Notes for the better part of two years and love it. I have used Obsidian and similar markdown apps, and I find it frustrating to add images due to the need to store them in a separate folder and reference them instead of just pasting them into the page and being done with it. To me, that's a barrier for notes when I'm trying to brainstorm. I really do like markdown, but it doesn't work with my though process.

I have a sync server setup at home (with no outside access) and do my main writing inside my network. For notes on the go I use the Notes app on my iphone (its quick and easy) and then drop the notes into Trilium when I get home.

I use silverbullet, it is great for tasks and notes! https://silverbullet.md/ - the manual itself uses it, so it is both a manual and a demo page

Perhaps not as full featured as the others, but I host wiki.js for my knowledge base on my local server.