When a file has been attached to a message and sent, that file will appear in the conversation’s message thread. By default, these attached files may also have preview turned on. For example, if it’s an image, you will be able to view that image within the app.
Additionally, there are some files (such as images and documents) that you can view full screen within the app. If you are viewing a file in fullscreen mode on the RingCentral desktop or web app, you can leave comments for others in the conversation to view.