On the home page of the app, in the Today's Readings section, I hit the plus button, then Daily Devotional, but the book I'm looking for (New Morning Mercies: A Daily Gospel Devotional) isn't listed. Is there any way I can add it?
It depends: is it a Logos edition resource (rather than Vyrso)? Is it the type:calendar devotional or something else? If the resource isn't the right edition/type, you will have to manually create a reading plan.
The resource you refer to (https://vyrso.com/product/49367/new-morning-mercies-a-daily-gospel-devotional) is a Vyrso book and they don't get the necessary date tagging to be added as a Daily Devotional.
Thanks, that's helpful. It's a Vyrso book.
One partial workaround for such things is to convert the Vyrso book into a Logos Personal Book (PB) and including the tagging by yourself. I've once done that for another such calendar devotional, it's pretty straightforward. Not that it's only a partial solution as PBs work only on your desktop and won't be visible on the iPhone/iPad.
Another workaround could be to make a reading plan for the book.
