PDF problems (some came with recent update).
(1) No scroll bar capability when reading the document. Fine for a dozen pages; a nightmare for a 400 page book.
(2) SEARCH capability is missing. This is a fundamental need in a PDF viewer. If you had the search capability, I might not complain so much about the missing scroll.
(3) Annotations inconsistent. Annotations are cute, and might be useful, but in some cases, once applied, they cannot be removed or edited. They now appear to be a permanent part of my document. On a different document, I was able to locate, edit, and delete them. On another, once applied, they are un-editable.