DateDetective app for iPhone and iPad

DateDetective deals with calendar dates.

DateDetective has two sections:

***** "Holidays" helps you find out the exact date and day of week of the American holidays and other holidays known or celebrated in USA (like "St. Patricks Day" or "Cinco de Mayo").
Some holidays have a fixed date, like Christmas, but most of them dont. Easter date, for instance, varies from March 22nd to April 25th. Thanksgiving also varies in date; its the 4th Thursday of November.

***** "Day Of Week" helps you find out the day of week (Monday, Tuesday ...) of a given date (like your birthday). Its very friendly user interface is self explanatory. Just pick a date and the day of week will immediately be displayed on the screen.