It would depend a lot on the tablet of course, whether or not it can have a folder full of files copied easily to it, and how easy it makes it to edit them, but do have a look at the external folder syncing feature, documented in the user manual in §14.3, Synchronised Folders.
This feature was made for what you are doing! When you copy the folder of files back into the original location, from the device, and open Scrivener, it will alert you to changes being detected and you can sync them in. A collection will be created listing all of the items that were changed, and by default it also takes Snapshots so you can compare, and see line by line revisions.
If the tablet has some kind of cloud connect, then you use that instead of the copying back and forth method.
Do you also use an external editor at times?
Quite a lot! I write using Markdown, and often in the very early drafting phases it is nicer to use a dedicated Markdown editor right alongside Scrivener (which is mainly be used for the outlining and organisation at that point). Here is a post demonstrating a typical setup.