Can the person viewing the submissions add photos or responses later?

Sometimes a person submitting may click to be confirmed etc.

Can the person viewing the submissions attach an image or add information after it's been submitted?

Hi,

You can indeed update your submission data at a later time. 

1. While on "My Forms", select your form and click "Submission" button from the top menu.

2. On bottom of the submission page, you will see the list of all submission.

3. Select the submission you want to edit and click on the "Edit" buton on top right.

If you would like to allow the person filling out the form to update their submission at a later date, that is possible as well.  Here is our guide on how to do so:

http://www.jotform.com/help/40-How-to-Let-Users-Update-Their-Form-Submissions-at-a-Later-Date