Yesterday Dropbox Inc has announced a new feature of their Dropbox desktop application where users is now able to add comment in publicly shared folder and other uploaded files.
After the user uploaded a files onto dropbox. clicking on the file name will have the comment section shown on the right as shown above. Different users can now make several comments on documents and photo uploaded by the original user. Alongside with the online edit feature with Microsoft, documents editing and reviewing will be a more easier thing to do in Dropbox.
This feature is currently available on Dropbox desktop interface. It could take some time before Dropbox officially rolling out this feature on the mobile interface