Hello, I have been playing this game for two days so far but this "feature" really bugs me. Don't you think the same, that it would be great if there was a sound when some production is complete? I find it quite stressful having to stare at the phone not to miss the glowing green rectangle, because you really need to do it fast in many situations. Having a simple "ding" when something is done would be great because then I could enjoy seeing dwellers conversation while zoomed to some room or do looking at statistics of happiness and such, but no - I gotta have the overview displayed all the time to be effective which is silly.
It would be also pretty good to have working count down in the dwellers list. There is just very rough time estimate and I found out that it does not even change from <1min to DONE when it is done, so that does not really work as I would expect and how it is in similar mobile games.
EDIT: of course that one "solution" is to switch out of the game and just watch my phone's notifications which will tell me that production is complete :-]
EDIT2: but it seems these notifications come from time to time only anyway...