The link I sent is to a swift implementation but the function is still emailMesh() in MeshViewController.swift. I added the capability to store scans as well as upload them to dropbox or email. I think it is set up to connect to the file system through iTunes, if not it is just a single entry set to YES in the Info.plist as highlighted below
Looking at MeshViewController.swift it should be clear where and how to save the scans off to the file system. If you download the scans through iTunes then you only need to add code to save files with unique names for each scan and also a way to delete the old scans off, you cannot do that from iTunes. I like adding the date and time to the filename to make them unique and you also see the order they were taken in.