Google Drive is Google's file sync app that lets you store all of your files online alongside your Google Docs documents, and keep them synced with all of your devices.
Add readable photo text to requests before the approval handoff.
Give approvers the text from a linked document photo right on the request, with unclear passages marked for a closer look.
Add follow-up files to the original approval item.
Your reviewer sees missing files on the pending approval item, even when a requester adds them after the review starts.