ActiveForms offers 2 ways to present a date field—with a calendar:
or as three selection fields:
When should each one be used? In theory, there is no difference and you can use them interchangeably. In real life, however, each one is filled in differently, and ergonomics requires that you select the presentation type carefully.
In short, the calendar is better for specifying dates close to the current date. When the calendar is displayed, you can see the current month and it takes a single click to specify a date. That is why the calendar is perfect for contact forms in the “suggested appointment date” field. Most users will want to specify a date in the near future, which is immediately available.
The day-month-year selector field works better with more distant dates. A classic example is the date of birth. It takes three clicks to specify the exact date, without having to open the calendar.
The calendar is also useful when:
Historical dates and fixed ones (like dates of birth) are, of course, not among those cases.
In some special cases there can be other clues for selecting date field types. For example, if you know that form field values are often filled with Copy & Paste operations, it is better to use a Date Picker field, which—apart from the calendar feature—is a regular text field.
And why would you go to such lengths—as usual for usability that supports conversions!