Exploring the 71 IDS Restored Articles - TITAN-71B - John Baker

[Sylvain Cote]

iOS & iPad devices does not have access to the file system, applications are sandboxed.
PDF can be seen in mobile Safari if the file is shared directly through HTTP/HTTPS from a web server.
If you have an iCloud account and iCloud Drive is activated, you can download the zip file to the iCloud drive, then extract the file there, then you can open the file from iCloud through HTTPS, all within mobile Safari.