title: Corona sdk best way to go about build.settings and config.lua
body: <p>I am trying to make a math game but I have come into several problems.  The first is that In the android emulator that comes with corona I have black space at the top and bottom.  These are my files:</p>
  
  <p>config.lua:</p>
  
  <pre><code>local aspectRatio = display.pixelHeight / display.pixelWidth
  application = {
     content = {
        width = 320
        height = 480
        scale = "letterBox",
        fps = 30,
  
     },
  }
  </code></pre>
  
  <p>build.settings:</p>
  
  <pre><code>local aspectRatio = display.pixelHeight / display.pixelWidth
  application = {
     content = {
        width = 320
        height = 480
        scale = "letterBox",
        fps = 30,
  
     },
  }
  </code></pre>
  
  <p>It shows my image correctly but I get black at the top and bottom.  I read tutorials about these to files, but they are so complex.  What is the easiest way to may these files work?  The tutorials I read also tried to find each device that this app could be running on and makes the settings accordingly, but id like to be more cross-platform and not have to update the app every time their is a new size of device.</p>