Jake has created a excellent tool for displaying an attached image inside of a popup window in AGOL. It creates a 15 day Token and you can run his Tool every 2 weeks to automatically renew your Tokens (not necessary if your application is public).
I would like to see enhancements to allow for multiple attachments to be updated to multiple fields instead of just the current one to one relationship.
This could really streamline the workflow when you have 3,4 or 5 attachments and you want them all to display in the popup window. Jake Skinner