The storage is definitely the most complex and important part of an application setup, once this part is completed, one of the most problematic parts could be solved.
Mounting a S3 bucket into a pod using FUSE allows to access data stored in S3 via the filesystem. The mount is a pointer to an S3 location, so the data is never synced locally. Once mounted, any pod can read or even write from that directory without the need for explicit keys.
However, it can be used to import and parse large amounts of data into a database.
..read on Shared S3 Storage how to configure it.