Is there a way to display to the survey user, the remaining characters available for a text input field? Similar to what one sees when authoring a tweet in Twitter?
Accepted Solutions
That depends on whether you specify a name for the database field name. Below only the second note is stored:
| type | name | label | calculation | bind::esri:fieldLength |
| text | example | Example | 500 | |
| note | Count | concat(string-length(${example}), ' of 500') | ||
| note | exampleCountStored | Count Stored | concat(string-length(${example}), ' of 500') |
As can be seen in the Schema Preview:
As can be seen in the example above, you can also change the length of a string if needs be using the bind::esri:fieldLength column.
More than welcome Dan 
Just a quick note to say that this functionality is available in the web client (i.e. when the survey is viewed through a browser):
https://survey123.arcgis.com/share/f2159e91f5c24f3495753fe68a9040f5
and the next generation forms (currently in beta)
https://survey123.arcgis.com/webclient/f2159e91f5c24f3495753fe68a9040f5
It's just not available in the mobile app yet.
Michael:
Thank you for your time and input to this thread. Your solution, above, works fine, but is not dynamic, that is, does not show the user how many characters remain in the limit as they are typing.
Also, your comment on "note" items being committed to the database as asked by Dan McIlroy. It appears to me, from my Survey123 forms, that a "note" item is not by default committed to the database when the "name" field is populated with a value (see first screen capture). If a "calculation" is included with the note, then the note is committed to the DB (see second screen capture).
Note without "calculation"
Note with "calculation"
