Just discovered a very practical FREE iPad App which returns the day of the week for any date (past or future).

In performance, you can hand out the iPad to the spectator who can select a date of their own choosing, or can spin the tumblers for a random date.

This is ideal for Day-For-Any-Date workers and can be used in conjunction with any DFAD system (e.g., Scott Cram's Day One method, or my own Speed Dating).

Be careful with historical dates, however, because the app will make Gregorian calculations for dates before the Gregorian Calendar was introduced.

The App is called "Date Calci Pro" from Permeative Technologies. It will also calculate the number of days between any two dates.

Mike

Great find, Michael!

It should be noted that's an iPad-only app, so it won't work on an iPhone or iPod Touch. It may also only be free for a limited time, as it just came down from $4.99 today.

Here's some links:
Description: http://appshopper.com/utilities/date-calci-pro
App Store link: http://itunes.apple.com/app/date-calci-pro/id467570945?mt=8

I've also found that Wolfram|Alpha works well for the day-for-any-date feat, as anyone online can use the app or the site.

Here are some links for Wolfram|Alpha:
Site: http://www.wolframalpha.com/
Wolfram Alpha Apps for iOS/Android/nook/Kindle: http://products.wolframalpha.com/mobile/
iOS App Store link: http://itunes.apple.com/app/wolframalpha/id334989259?mt=8

...and some examples of using it for dates:
1992 calendar: http://www.wolframalpha.com/input/?i=1992+calendar
August 1992 calendar: http://www.wolframalpha.com/input/?i=August+1992+calendar
August 21, 1992: http://www.wolframalpha.com/input/?i=August+21%2C+1992
Between two dates: http://www.wolframalpha.com/input/?i=Sta......to+today

Since you mentioned our respective books, we should link to them, too:
Speed Dating: http://www.lybrary.com/speed-dating-p-119767.html?affid=2169
Day One: http://www.lybrary.com/day-one-p-137029.html

There is also my free online Day for Any Date tester at

http://www.mindmagician.org/daydate.aspx

This enables you to test your speed as well as accuracy.

An offline version of this tester is included with my Speed Dating ebook.

Mike

Quick Note: Date Calci Pro has returned to its previous price of $4.99, as of Sept. 27th.

Taking a look at the price history (http://appshopper.com/utilities/date-calci-pro), it was also free back in June, so it's possible that it will be free again in the future.

If you go to the link and create an account at AppShopper, you can put it on your wish list so you'll be notified the next time it's available for free.

For an iPhone App that does the same job, "What Day is That?" by Nicholas Cooke is very good (GBP 0.69 or, I guess, USD 0.99). Excellent, practical interface. You can safely ignore the review that says the calculated days are one off. Also works on iPad.

Mike

What Day is That? app:
Description: http://www.nicholascooke.com/Day/day.html
iTunes Link: https://itunes.apple.com/app/what-day-is......387?mt=8

You can find a few more for free or pay here.