Is it possible to add a new Google Calendar event using a free form input? Dumping in a chunk of unstructured English and having the app attempt to extract date and time automatically, instead of entering data into form fields?
An example would be writing "Saturday, 28 December 2013, 11:55 PM" and having the correct date and time pop up in the date and time fields.
unstructured English
This really depends on what you mean by "unstructured". However, your example is reasonably structured and this works as intended using the Google Calendar gadget (enable the "Lab experiment") in gmail.
At the bottom of the calendar gadget there is an "Add" link that gives you a single text box in which to enter the details of your event. Then click the "Quick Add" button.
"Saturday, 28 December 2013, 11:55 PM"
This creates an event at the specified date/time that lasts 1 hour (by default). The duration of this event is taken from the "default meeting length" as set in your Google Calendar (from 15 to 120 minutes).
This is called Quick Add and it is described in the help pages at https://support.google.com/calendar/
You press the caret on the right side of the red Create button and write your free form input in the box that pops up. Alternatively, the box is displayed also by hitting q on the keyboard.
