I know it has only been a couple of years since this suggestion, but was interested if there has been any thought to incorporating the 'send to kindle" feature?
Yes, it is Kindle only, but the number of kindle ereader devices out there probably rival android/epub devices.
And is it a 'mobi/azw3' issue in any way? The sendtoemail is just picking a file and sending it, isn't it?
In any case, Ubooquity is a fantastic program, but those I share my books with are actually split kindle/android users and those kindle folks are bugging me about this!!
The thing is, during those two years, my backlog kept growing.
So I now have even more features I want/need to implement before considering system specific features.
And the two reasons explained above still stand (although you're right about the file format having no impact on the feature).
So I'll decline again, sorry.
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