This review application must have email notifications to both sender and recipient of posted comments.
The image must be able to be enlarged so that copy can be read.
The comments must somehow be linked or pointed to highlighted or noted areas of the page.
Multiple seqential versions of each file must be shown. For example, I send a file to customer for review. they ask for changes. I place those changes. Now a new file (lets say version 2) needs to be part of the revision process.
Anything you can do to implement these things would be very helpful
Finally, an approval button. Seems like a no brainer, but it's not therre.