Gallery for Ultimate Member is an amazing plugin that enhances any Ultimate Member enabled Social Network. With the option to add both photos and videos, it is a great way to add content to the site. From the media modal, users can drag and drop photos as well as paste links to YouTube/Vimeo videos then add a caption to them each.
With the Comments addon enabled from the Gallery Settings, users will be able to post comments for individual photos. The owner and administrators will have the ability to delete comments as necessary. Another addon available is the Activity Wall addon which posts new albums to a the activity wall.