I am considering using DropBox to work with Beta Readers. Each would have access to their folder where they could download the book and insert the edits into the document then save it back with their changes.
Mostly, it would save me time and some confusion. I find Gmail occasionally sends emails with Word attachments directly into my spam folder or trash. I know a few beta readers have complained about this too. I’m a big fan of streamlining things and making them easier.
However, I know not everyone has internet at their house due to rural internet restrictions.