<phpedinei>: The good folks at Corona have, sadly, been repeatedly reluctant to fix these sharing problems.
In the Android Facebook sharing situation, <davebollinger> noted in November it would be only a handful of code. But there’s been no response in this thread since then.
In the iOS sharing situation, there are 10 lines of ObjC code that need to be added – to support a feature that is the most-requested on Corona’s official request forum. But a few days ago Walter and Brent both pointedly declined to say it would be added: http://forums.coronalabs.com/topic/53371-supporting-ios-modal-share-action-sheet-airdrop-print-add-to-home-screen-add-bookmark-add-to-reading-list-etc/
Given this reluctance over multiple months to add two trivial sharing features, my guess is Corona management views their absence as either unimportant or a way to convince developers to pay considerably more for Enterprise. That’s their right, of course, but it would be nice if developers were told so forthrightly.