Regarding iOS file deletion rules
I'm just curious, and wondering if someone can answer this for me.
As an example; I have 2 apps installed on my iPhone, Kobo (for books) and Rdio (for music). Both of these apps download and store content on the phone. Every now and then I'll open the Kobo app and it notifies me that the OS has deleted my downloaded books in order to recover some space. The Rdio app never does this; the music I sync to my phone through Rdio stays put, and essentially the OS leaves it alone.
Now it's not an issue of space, as I usually have plenty of free space on my phone, so why does the Kobo data get deleted while the Rdio data does not? Is this something the developers of the apps are in control of? Or does iOS simply treat certain data differently, depending on what type of files they are?
Again, just curious.