[fduniho]

I was having the problem that the collections I had created in the Kindle app on my Likebook Mars were not showing up my Kindle devices.

As a first test, I added two books to the Philosophy collection over the web. They showed up in this collection on the app but not on my devices.

As a second test, I tried to create a Philosophy collection on my Paperwhite 5. It wouldn't let me, saying that there was already a collection by that name in the cloud.

As a third test, I created a Test collection online and added a book to it. This new collection showed up on my Likebook Mars but not on my Paperwhite 5.

As a fourth test, I added a new book to the Science collection through my Paperwhite 5. It showed up in that collection on my Likebook Mars, but my Paperwhite 5 still cannot sort or filter by collection.

As a fifth test, I created a new collection on my Paperwhite 5 called Test2 and added a new book to it. This collection had a star next to it when it showed the lists I could add the book to, and after I added the book to this collection, this new collection showed up on both my Paperwhite 5 and my Likebook Mars. I did not see it show up on my Paperwhite 4.

As a sixth test, I added another book to Test2 through my Paperwhite 4. This showed up in Test2 on my Paperwhite 5, though not on my Likebook Mars.

Finally, I clicked ALL instead of DOWNLOADED, and I found I could access my collections. I used the Paperwhite 5 to delete the Test and Test2 collections, and by going to a collection, I was able to use the menu to add a collection to the device.

ADDENDUM:

I answered my own question, but when I tried to edit the subject line, it ended up posting it instead.