Currently, if I upload a PDF file that has links in it (for instance, the table of contents), when I press the link, it will automatically take me to the page I selected. However, there is no way for me to go back immediately to the previous page I was on; this is cumbersome, as I work with laws and often have to jump back and forth between addendums, and having to manually navigate back to the page (or try to remember what page number I was on) is less than ideal.

Noteful has a system that works similar to this, and Kindle has had a "return to previous page" function for a very long time as well. I believe such a feature would be incredibly useful and easy to integrate.