title: Slider's thumb form change. C# XAML 8.1
body: <p>I'm making Windows 8.1 phone app using Visual Studio 2015 and C# XAML.</p>
  
  <p>I want to change the slider's thumb to a "round" style, like below.
  Can is be easily changed or not?</p>
  
  <p>Please help me change the slider's style.</p>
  
  <p><a href="https://i.stack.imgur.com/1CTHg.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/1CTHg.png" alt="I want to change Slider&#39;s style C# XAML 8.1"></a></p>