Soda PDF Desktop
The recent documents list is based on information located in the registry of your computer. This means that it will only be visible to anyone using Soda PDF while logged in as a specific Windows User. It shows the most recent files you have opened in the order they were opened.
People opening the document on a different computer will not be able to see your list.
Click on the Home icon. This will show you the most recent files you have opened. You can clear this list at any time by clicking on Clear All. 
Soda PDF Online
Soda PDF Online does is not an application that installs onto your computer. Instead you access it directly within a web browser.
The Recent Documents list in Soda PDF Online serves a different function than in Soda PDF Desktop. Whenever a file is opened within our web application, it is stored temporarily in our system for 24 hours.
These files are linked to the specific user who logged in. No one else will be privy to the recent documents list.