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These are good questions, I believe something that may help you out is found described and documented in the user manual PDF, under §14.3, Synchronised Folders. I don’t have as much to add with regards to dictation, as that has never been a mode of input that has worked for me.
Before going down the rabbit hole, the concept here is pretty simple: Scrivener can be instructed to dump the contents of the binder (selectively or fully) to text files, which can then be edited in any program, synced off-system, zipped and unzipped, etc. It’s pretty basic, based on modification dates and per-paragraph diffs, so it’s all pretty safe. But, with the right combination of features, it can also be an inbox—a role I’ve used it in on many occasions, as some of my projects are just too big to open and close whenever I think of something in relation to them.
The user manual goes goes over the settings by and large, but here are some links to discussions that go over its usage in a more practical way, and in particular for its use primarily as an inbox mechanism rather than a two-way drafting tool.
- Setting up an inbox using the folder sync feature. As I note at the very top of that post, the easiest answer here is indeed to just use the scratch pad feature. It has a setting to point the folder anywhere, which can be a cloud synced area. As with external folder sync it can be set to plain-text with the .md extension. It’s okay, and it does all the important things, but if you’re like me you’ll want something a bit more than that at some point, and that feature is intentionally dirt simple and global rather than project oriented.
- Setting up a project as an inbox or general scratch pad: while this technique works with any active project, and you can have multiple inboxes on your phone that route notes to the right places, I find having a place for “everything else” is useful, and a project setup like this is good for it, as it pares down the desktop interface enormously, to something not much more involved than the Scratch Pad feature itself.
And some adjacent topics: