Microsoft Office Outlook, Todoist, Things, ToDoList, Workflowy, Habitica, Taskade, Org mode, MyLifeOrganized, Desktop-Reminder, Task Coach, Remember The Milk, sleek, GoTasks, OpenLoopz, Makagiga, EdenList, Concenturio, DevTodo, cloudList, MyAsana, ActionComplete are some alternatives to Top Task List.