How much working time is there between the dates?
Just specify a couple of start and end fields. These can be any issue fields containing the date and time (system and custom fields). The application allows you to quickly and easily implement the calculation of the remaining, elapsed or just time between dates.
Despite its simplicity, you can use work calendars, JQL search and sort. The data will be updated in the background, so you will always have the most up-to-date result.