Thanks to: King contribution
Source: Apple App Store
Horology is a date/time calculator and converter.
* Compare two dates: enter two dates and see the difference in years, months, days, hours, etc.
* Calculate a new date: enter a starting date and add or subtract years, months, days, hours, minutes, and/or seconds to see what the resulting date will be.
* Convert time values: enter a value and see what it converts to, e.g., how many seconds are in 7 days, or the number of hours in a month.
Horology also supports multiple calendar types, such as Gregorian, Buddhist, Hebrew, Islamic, Japanese, etc.