- Don't try to have a touchscreen UI on desktop. Make right clicks do something useful in every situation. There are two types of touch in IPhone for some time now, so maybe don't live in the touchscreen past in a desktop interface...
- Don't copy IPhone ultra minimal design style. I have no border for the Teams window, I don't know where it ends and the window under it starts because there is no border. Horrible. IPhone UI design is now so bad that only past experience from when it used to be good allows people to know how to use it. Don't copy it and don't let anyone who does tell you they are a good UI designer, copying bad design is both lazy and demonstrates an inability to recognize bad design.
- Write user stories for how users use your tool currently and then MAKE THEM SHORTER STORIES then change the tool to make them true stories. A typical user story taken from my own usage goes like this: I start out knowing what I want to do, I flail around unable to figure out how to do it, I give up and use email instead. If software engineers struggle to use your tool it has a bad UI. A right click menu that gives options to do everything that can be done related to what was right clicked on would be a great alternative. Having two ways of doing things is better for discoverability than only one, particularly when the one way is a pain to figure out.
- Make it so that the chat icon in the left bar doesn't disappear and reappear randomly and initiating a chat that fails to work gives an error message at least. I don't know whether this is a mis-feature or a bug. Chat is the primary function of this tool so if it disappears or doesn't work there should at least be a clue as to why. Crashing would be better. Microsoft has trained its users to understand what crashing means, at least.
- You have some kind of overflow bug when the chat history gets too long where it scrolls to random (overflow) position in the history after updating with a new message. Fix it.