Add a status-field to a task
Expect for an indication that a task is completed or not, there is no way to give a task a status, like for instance 'on hold', 'busy' or 'rejected'. Even neater would be if the user could define his own statuses.
This feature is already available. To set a status to a task, simply type @busy or @waiting or @on_hold or any other word you prefer and such task will have a label with this name attached to it. You can then click on this label to see all tasks that have the same label or include or exclude them in search queries.
To find our more information about using labels to monitor a task status, please check this post on our blog: https://todoist.com/blog/2013/02/use-task-labels-to-monitor-task-status/
This is actually a solution that I use.
I think it would be preferable to an external field "in progress", "pending" (can rename the state) to a filter with one click.
This could take the form of filters in a column on the side (eg e-commerce) with filter date projects list, keywords with a search field.