App: HolyDates
Developer: Tom Stankey
Genres: Reference, Lifestyle

Version 1.10
No Advertisements, No In-App Purchases
Did you ever need to look-up when Easter Sunday or Passover will be this year? Even though many of the religious holydays occur on the same date of the Hebrew calendar every year you may not know the corresponding date on the Gregorian calendar. HolyDates provides a quick answer to these questions.

HolyDates uses algorithms provided by Jean Meeus in his book, “Astronomical Algorithms” second edition. His methods have become a sort-of standard for these sorts of computations.

The information and functionality provided by HolyDates is divided onto several screens.

The Main Screen:
The day and date for eleven holy days are shown on the main screen.
•	Passover
•	Easter
•	Unleavened Bread (aka .Matzo) – seven days in length
•	First Fruits (two methods for determining this date)
•	Shavuot (two methods for determining this date)
•	Pentecost
•	Rosh Hashanah (aka Yom Teruach, Feast of Trumpets, New Year Day)
•	Yom Kippur (aka Day of Atonement)
•	Sukkot (aka Feast of Booths, Feast of Weeks, Feast of Tabernacles)

The Julian Day Number Screen:
Julian Day Numbers are used by astronomers to keep track of dates or perform date-related computations.  HolyDates provides a separate screen for converting between the two systems.  You can:
•	convert Gregorian Dates to Julian Day Number
•	convert Julian Day Numbers to Gregorian Dates

The Information Screen:
This is the HolyDates help file that provides additional background information. The origin of the modern calendar system and how HolyDates works are discussed.

Release notes:
An  “Increase Year” button  and “Decrease Year” button were added to the main screen.
Corrected an error whereby years with fewer than four digits can be entered.