More and more, the 3-line and Pinyin PDF files will be used on computers, including mobile devices such as the iPhone, the iPod touch, and the iPad, rather than printed out on paper. So, to take advantage of the computing power available on such devices, bookmarks and links have been added to some of these PDF files to make it much more quick and convenient to find the material one is looking for while using them. PDF bookmarks and links are especially helpful on iPhone-sized mobile devices, since they remove the need for a lot of the tedious manual scrolling that would otherwise be required because of the relatively small screens on such devices.
The PDF files named with “LinkNav” (“Link Navigation”) or “LN-A” (“Link Navigation-Annotation”) have been enriched and fortified with PDF bookmarks and links. These work like web hyperlinks, immediately taking you to the destination linked to when they are clicked or tapped on. For example, calling up an LN-A file’s list of bookmarks and clicking or tapping on the bookmark for chapter 7 will immediately take you to the beginning of chapter 7. Similarly, in an LN-A file’s table of contents, clicking or tapping on the link to chapter 7 will also immediately take you to the beginning of chapter 7. Either way, you are saved from having to scroll there manually.
In Adobe Reader, bookmarks are displayed in a navigation panel, and in Preview on Mac OS X, they are displayed in the Sidebar. Links in the LinkNav and LN-A files are displayed using purple text. (See the PDF Annotation (Notes & Highlighting) page for more information on PDF annotation.)
This 32-second video screen recording shows how PDF bookmarks and links have been implemented in the LinkNav and LN-A files:
(A larger version can be downloaded here.)
Note that not all PDF viewing apps for the iPhone/iPod touch or for the iPad support bookmarks and links. GoodReader and Documents have good support for PDF bookmarks and links. They even allow you to add your own bookmarks.
For more information on using 3-line material on the iPhone or iPod touch, see the 3-Line Material on the iPhone and the iPod touch page. For more information on using 3-line material on the iPad, see the 3-Line Material on the iPad page.