Starting from version 7, it is possible to have two types of toolbars based on your needs:
The single line version will take less screen space, however you won't have one touch access to additional viewer options menu such as save a copy, add/remove page etc.
The two line version takes more space, however you will have constant access to additional viewer options.
To toggle between the two, you can locate the "Use Single Line Toolbar" switch in the app settings.