That is the way iOS works. Files are associated with Apps, and generally they aren’t shared with other Apps.
However an App like FileBrowser may be able to find the file, and the use “Open In” to open it in another App. I can’t remember how flexible is was as I haven’t used it in a while.
Also if you haven’t, take a look at the video I mentioned in your other thread, that is the “How To Use My Passport Wireless with iOS”, here: https://www.youtube.com/watch?v=Ua6O6DtG5Oo&list=PLwcbXPYucCc0jtWyJtV_Z9cPvPBC5dZt4 as it has some comments on Uploading photos from an iDevice to the MPW, and covers the My Cloud App better.
Also read my other comments in this thread: http://community.wd.com/t5/My-Passport-Wireless/Connect-to-internet-with-iphone/m-p/843268#M795
