I am currently trying to organize my notes. The old 'system' is a pain, and getting everything centralized makes it easier to find things. Notes, snippets, bookmarks, and so on.
What strategies or software are you using? My stuff is also kind of spread out right now: informal notes in loosely structured folders, formal stuff in a zettelkasten directory, bookmarks in a recfile, and work stuff in a Zim notebook.
Do you know https://logseq.com/ ? - I think it is considered an alternative to Obisidian. Had been using it for a while, was great, but it was almost too much work to organize everything.
The vaults created on your device are stored in clear-text. I have seen discussions about encrypting the vault yourself using cryptomator or veracrypt.
I believe they have E2EE for the remote vaults if you subscribe to Obsidian Sync.
You can use cryptomator to encrypt your vault if you are storing it on your cloud drive but i couldn't find out an easy way to enable sync that with my android device.
Haven't found my perfect solution. The current goal is get everything together and see what I really need. Most likely a single .md file that I can encrypt and sync in my machines, but not sure yet.