The only distinction between Acrobat Reader running stand-alone and Acrobat Reader running inside the web browser is whether a user is allowed to Submit data to a Web Server or not. Since Acrobat Reader does not have the functionality of a web browser built in, it cannot submit to a web server when it is running stand-alone.
Reader can only submit when running inside the web browser as a plug-in.
Otherwise, users will find that they can fill out and print the document, but not much else. Must pay for license 1.2. Ability to print data with form. Ability to save data with form. Acrobat Reader Plug-in 2.1.