Suggestion : filtering out non saved books

I have a massive library and hate how long it takes to load when I save for offline use just a few for regular access

As Graham wrote, you just need to use local: to filter for downloaded resources... But I am curious: What do you mean by "I hate how long it takes to load"? I don't see a correlation between filtering for downloaded resources, and how long (what?) takes to load? 

so each time I open the app, I have to retype it? On the desktop that seems reasonable, but on a mobile device, it seems more reasonable to just have it as a way of filtering. 

filter strings in the library seem to stay there until explicitly changed.

are you not seeing this?

And, Alabama's question above is a good one. Can you expand on the problem you are seeing?

so each time I open the app, I have to retype it?

Nope... you shouldn't have to... unless, perhaps, you kill the app (via multitask bar) or you run out of memory.

Even that does not delete the Local: filter. I regularly kill apps when I will not be using them for a few hours—or even less time—and the Logos library filters remain as I typed them.

Here is a screenshot from my phone. It works the same on iPad... (unless you are on a REALLY old version of the app).