iDateConvert is a simple but extensive utility for converting dates between different actual and historical calendars. It currently implements more than 50 calendrical and day numbering systems, along with some of their (local) variations: the Afghan Calendar (Arithmetical), the ANSI Date, the Armenian Calendar, the Aztec Calendar, the Bahá`í Calendar (Western and Future), the Balinese Pawukon Calendar, the Chinese Calendar, the Coptic Calendar, the Egyptian Calendar, the Ethiopic Calendar, the French Republican Calendar (Original and Arithmetical), the Gregorian Calendar, the Hebrew Calendar (Arithmetical and Observational), the Hindu Calendar (Solar and Lunisolar; Old, Modern and Astronomical), the Islamic Calendar (Arithmetical and Observational), the ISO Calendar, the Julian Calendar, the Julian Day Number (Standard, Reduced, Truncated, Dublin and Modified), the Korean Calendar, the Lilian Day Number, the Mayan Calendar (Spinden, Thompson and GMT correlation), the Persian Calendar (Arithmetical and Astronomical), Rata Die, the Roman Calendar, the Tibetan Calendar (Phug-lugs), the Vietnamese Calendar, and the Zoroastrian Calendar, with more calendars and localizations being planned.

USE and FEATURES:

The use of iDateConvert should be straightforward. The default conversion pane ('Date Conversion') allows to choose the source and target calendar for conversion, and provides a short description (via the 'Info' button) for each selected calendar. Due to size limitations of the iPhone interface, default date selection by numbers only is provided within a reasonable range between year -10,000 and 10,000 in the Gregorian Calendar. However, as many calendars work with names (not numbers) for their various components, an alternative date selection method can optionally be chosen in the 'Preferences' pane. As the number of implemented calendars in iDateConvert is rather large, and not all calendars might be of interest for the User, individual calenders can be enabled or disabled in the 'Preferences' pane as well. Finally, in addition to the default date conversion interface (via 'Date Coversion'), a clean list of converted dates for all enabled calendars is provided by selecting 'Date List' in the bottom menu.

NOTE concerning calendrical conversions:

Despite countless attempts in the past and present to standardize the various calendrical systems in existence, exact conversions are still subject to many variations and local rules, which render calendrical conversions a rather tedious and difficult task. The calendrical algorithms used in iDateConvert are implemented from mostly original sources, and checked for correctness using 'Calendrical Calculations' (3rd Edition) by Bachum Dershowitz and Edward M. Reingold, the to-date most comprehensive and clear description of modern and historical calendrical systems. Although we tried to follow the most commonly accepted algorithmic definitions and nomenclature, we welcome each report of inconsistencies or errors for improving the usability of iDateConvert.

We hope you enjoy the use of iDateConvert.