My (rather old) Samsung mobile phone did not accept 2015 as calendar year after reset due to empty battery.
Therefore I made the program 'IdenticalCalendar' which calculates which year in the past had an identical calendar.
By setting that year, the day of week will be displayed correctly. Enter the desired reference date after program start.
The program has been added to the Dropbox-folder.
The library 'date functions' has been extended with the function 'IsLeapYear(index)' which is required for this new program.
Also the '-ReadMe' file has been updated.