title: Converting all text to lower case in Objective-C
body: <p>I have a textfield in my iOS app where the user is supposed to input some text. But I was wondering if there is any way to convert the users input to lowercase letters.</p>
  
  <p>I remember in C# it was something like <code>Convert.ToLower</code> but I can't seem to figure out how to do it in Objective-C.</p>