Trello

-You can open multiple windows of Trello and there's no setting to disable this behavior. I have the app pinned to my taskbar and I prefer to click it instead of clicking the system tray menu and often results in dozens of apps running at the same time and flooding my system tray menu. -If you open the app, minimize to the system tray, open again from the system tray, minimize from the system tray and try to open again from the system tray, the app will glitch and become an invisible window. I'll update my rating when you fix these problems.

Notification used to work when the app was opened. Now it jut stop working altogether.

so happy to see this app. Have been using another app which is well done but lacks desktop notifications. However, the one feature it has this one is lacking is the ability to pin a shortcut to a particular board to start/taskbar/desktop. Add that and ill add the 5th star. Nicely done Trello!