[WorldMaker]

> On Windows Phone every reader app (not that there were many) had to have its own independent download because god forbid you have shared freaking storage.

That's not entirely accurate, even for Windows Phone at its most restrictive (7.x). The reader app would ask for storage apps and the storage apps would provide the files. It was quite common that the storage apps seemed like they would download multiple copies each file separately for each reader app, but that wasn't always the case. Unsurprisingly, some storage apps were just dumber than others.

Windows Phone 8.x and 10 opened up more direct file system access without going through an intermediary storage app, though of course possibly too late for the impression of stupid storage apps to linger.

ETA: Not that any of this currently matters given the current state of Windows on mobile devices. :(