This toggles between upper, lower, and title casing of selected text in Drafts app

Drafts App Case Toggler

/* 
  * To Title Case 2.1 – http://individed.com/code/to-title-case/
  * Copyright © 2008–2013 David Gouch. Licensed under the MIT License.
 */

String.prototype.toTitleCase = function(){
  var smallWords = /^(a|an|and|as|at|but|by|en|for|if|in|nor|of|on|or|per|the|to|vs?\.?|via)$/i;

  return this.replace(/[A-Za-z0-9\u00C0-\u00FF]+[^\s-]*/g, function(match, index, title){
    if (index > 0 && index + match.length !== title.length &&
      match.search(smallWords) > -1 && title.charAt(index - 2) !== ":" &&
      (title.charAt(index + match.length) !== '-' || title.charAt(index - 1) === '-') &&
      title.charAt(index - 1).search(/[^\s-]/) < 0) {
      return match.toLowerCase();
    }

    if (match.substr(1).search(/[A-Z]|\../) > -1) {
      return match;
    }

    return match.charAt(0).toUpperCase() + match.substr(1);
  });
};

// Addition by Dr. Drang to work as a Drafts keyboard extension.
// Convert selected text to title case.

// 2015-06-29 Addition by John Bielich to toggle casing with one button

var s = getSelectedText();

if (s == s.toUpperCase()) {
	setSelectedText(s.toLowerCase());
} else if (s == s.toLowerCase()) {
	setSelectedText(s.toTitleCase());
} else {
	setSelectedText(s.toUpperCase());
}