Exactly, I need to take lots of notes and beyond search and sync, I need it conveniently everywhere with me on all devices.

That's why I use Google Keep --- which is pretty terrible... except it's free, it's everywhere there's a browser, there's an app for it on every phone/tablet, and it works offline when I sometimes don't have internet connection.

Works ok since I write notes in plain text, with some markdown notation (but without actual Markdown support in Keep).

In the past, I've used Notational Velocity and other fancy things, but I find plain text is best. And now I need sync on all devices, so went with Keep.