Bookmarks are the key to effectively using Obsidian as a non-relational database. The virtues of approaching your notes this way are several, and I covered some in Freeing Your Thinking. In this article, I explore using Bookmarks to construct flexible, interactive Knowledge Trees to organize the information in your vault (not...
A lot of time and energy is spent on thinking about how to organize your notes into folders, and many people use Quick Switcher as the main way to both create and open notes, even to simply access some information. I started this way, too....
Syncthing is free, open source software that can be used to easily synchronize an Obsidian vault between your computer and phone/tablet. Not only free, but completely secure, private, and blazing fast. Here are links to an article I wrote explaining how to use it....