Many of the books I have bought in Logos can no longer be downloaded onto my Android phone. If I press the 'About this book' the message is, 'This book is only available online because it is not part of your Logos Bible Software library.' Two points:
Yes it is part of my library and I have paid for it; and
It used to download onto the same phone.
I have both Logos and Verbum and it happens in both, but not necessarily with the same books.
As well as slowing things down generally, reading online does not work at all when underground on the London Tube network.