Using it in the enterprise I work for. Messages never get aligned. Except for few hours after a fresh installation or a memory reset, you will start seeing numbers of unread messages piling up. Unfortunately, you may never know who was reaching out to you because, unless you go to the actual sender chat, you won't see any new message. Or, better, sometimes you do, most of the times you don't. It's unfortunate due how much the work has shifted to mobile devices.