title: Navigation buttons hiding Windows Phone 8.1
body: <p>I'm building a Windows Phone 8.1 application, and I'm facing the following problem. There are phones that don't have hardware navigation buttons(those for back, home and search). Those phones will shrink whole UI when virtual navigation bar appears, I don't want that to happen. So what can I do to prevent this? Internet seams not to know the answer(or I haven't searched good enough).
  This is what I mean when I say virtual navigation buttons.</p>
  
  <p><a href="https://i.stack.imgur.com/hO0cr.png" rel="noreferrer"><img src="https://i.stack.imgur.com/hO0cr.png" alt="enter image description here"></a></p>