I am all for making it easier for a developer to add features to many platforms at once. At the same time, I find a profound difference, not between OS's per se, but between (a1) devices with big screens, big keyboards & mice, and NO touchscreen -- MAC and Windows; (a2) devices with big screens, maybe big keyboards, maybe mice (iPad and other tablets); and (b) devices with small screens, tiny keyboards or keyboards on a touch screen (smartphones, whether Android or IOS). I would like my apps to display and receive input appropriately for those differences.
I note Evernote on Windows already displays differently on my portrait screen than on my landscape one (thanks, Evernote!). Where autotype and autocorrect are big hassles when I have a big keyboard (I am old enough to have started on a real, not even electric! typewrite), they can be very useful when trying to use my big thumbs on a tiny touchscreen keyboard on my iPhone (or my Samsung, when I had one of those; the touchstick helped a bit with accuracy at the expense of speed and convenience).
So please do not go "too far" in making the client "alike" on all devices. Please keep the size of the display and the form of input in mind (voice input and output is sometimes nice, but I am often in noisy environments or where noise from me or my device would disturb others).
Thanks for all you do.