There WAS a window, but I think it's closed already though. Google Docs and a host of Office-compatible Android/iOS apps made a go at it, and they made headway for a while. But Microsoft went ahead and made web and Android/iOS versions of Office that are at least as good as Google Docs and the various Office for Android apps I've seen, with far better Office compatibility than anyone else can offer (since they're running the same code as desktop Office under the hood).

Meanwhile LibreOffice is fighting the last war, with a thick desktop client using some custom cross-platform GUI toolkit that looks native on exactly nothing, no web app version and no real effort on mobile[1]. And it's fighting the last war badly at that -- not even people who write articles about switching to LibreOffice can actually switch to LibreOffice because they keep Word around for compatibility with everyone else in the world. Calc versus Excel is in even worse shape than Writer versus Word.

1) There IS an Android version of OpenOffice:

https://play.google.com/store/apps/details?id=com.collabora....

It's read-only and the UI is... subpar, however.