title: Release Mode and Debug Mode in VS
body: <p>I currently work on an Android application, and I messed around a bit with the VS.</p>
  
  <p>I was wondering, what are the real differences between the two modes? I did some research, but I didn't completely get the real differences and the advantages of each one, as well as when to use a specific mode.</p>
  
  <p>During my research, I came across those questions <a href="https://stackoverflow.com/questions/933739/what-is-the-difference-between-release-and-debug-modes-in-visual-studio">1</a>, <a href="https://stackoverflow.com/questions/90871/debug-vs-release-in-net">2</a> and <a href="https://stackoverflow.com/questions/367884/what-is-the-difference-between-debug-and-release-in-visual-studio">3</a>, talking about the differences between the two.</p>
  
  <blockquote>
    <ol>
    <li>Why debug mode runs slower than release mode?</li>
    <li>When releasing an application to Google Play, which mode should I use and why?</li>
    <li>Can I create my own mode?</li>
    </ol>
  </blockquote>
  
  <p>My app seems to be built fine in Debug mode, yet in Release mode I get a lot of warnings about "no debug symbols file was found".</p>
  
  <blockquote>
    <ol start="4">
    <li>What are those debug symbols?</li>
    <li>What is the "81" folder in the obj/Debug or obj/Release?</li>
    <li>I also noticed that sometimes, when switching from Debug to Release, some Resource.Id are not found, and I need to recreate the axml file for the layouts plus cleaning the sln. How can I prevent it?</li>
    </ol>
  </blockquote>
  
  <p>As I understood, debug mode uses some files that release mode doesn't need in order to run, I assume that the missing files are those "debug symbols"?. Maybe it's a problem with Xamarin or with VS?
  These are the warnings I get:</p>
  
  <pre><code>Warning     Directory obj\Release\81\android/assets contains Xamarin.Android.Support.v7.AppCompat.dll but no debug symbols file was found.          0   
  Warning     Directory obj\Release\81\android/assets contains Java.Interop.dll but no debug symbols file was found.          0   
  Warning     Directory obj\Release\81\android/assets contains Xamarin.Android.Arch.Core.Common.dll but no debug symbols file was found.          0   
  Warning     Directory obj\Release\81\android/assets contains Xamarin.Android.Arch.Lifecycle.Common.dll but no debug symbols file was found.         0   
  Warning     Directory obj\Release\81\android/assets contains Xamarin.Android.Arch.Lifecycle.Runtime.dll but no debug symbols file was found.            0   
  Warning     Directory obj\Release\81\android/assets contains Xamarin.Android.Support.Animated.Vector.Drawable.dll but no debug symbols file was found.          0   
  Warning     Directory obj\Release\81\android/assets contains Xamarin.Android.Support.Annotations.dll but no debug symbols file was found.           0   
  Warning     Directory obj\Release\81\android/assets contains Xamarin.Android.Support.Compat.dll but no debug symbols file was found.            0   
  Warning     Directory obj\Release\81\android/assets contains Xamarin.Android.Support.Core.UI.dll but no debug symbols file was found.           0   
  Warning     Directory obj\Release\81\android/assets contains Xamarin.Android.Support.Core.Utils.dll but no debug symbols file was found.            0   
  Warning     Directory obj\Release\81\android/assets contains Xamarin.Android.Support.Design.dll but no debug symbols file was found.            0   
  Warning     Directory obj\Release\81\android/assets contains Xamarin.Android.Support.Fragment.dll but no debug symbols file was found.          0   
  Warning     Directory obj\Release\81\android/assets contains Xamarin.Android.Support.Media.Compat.dll but no debug symbols file was found.          0   
  Warning     Directory obj\Release\81\android/assets contains Xamarin.Android.Support.Transition.dll but no debug symbols file was found.            0   
  Warning     Directory obj\Release\81\android/assets contains Xamarin.Android.Support.v4.dll but no debug symbols file was found.            0   
  Warning     Directory obj\Release\81\android/assets contains Xamarin.Android.Support.v7.RecyclerView.dll but no debug symbols file was found.           0   
  Warning     Directory obj\Release\81\android/assets contains Xamarin.Android.Support.Vector.Drawable.dll but no debug symbols file was found.           0   
  Warning     Directory obj\Release\81\android/assets contains Xamarin.GooglePlayServices.Base.dll but no debug symbols file was found.           0   
  Warning     Directory obj\Release\81\android/assets contains Xamarin.GooglePlayServices.Basement.dll but no debug symbols file was found.           0   
  Warning     Directory obj\Release\81\android/assets contains Xamarin.GooglePlayServices.Maps.dll but no debug symbols file was found.           0   
  Warning     Directory obj\Release\81\android/assets contains Xamarin.GooglePlayServices.Tasks.dll but no debug symbols file was found.          0   
  </code></pre>
  
  <blockquote>
    <ol start="7">
    <li>Are those warning really something I need to worry about when releasing an app? Can they cause any further bugs?</li>
    </ol>
  </blockquote>
  
  <p>I already tried:</p>
  
  <ol>
  <li><p>Deleting those files.</p></li>
  <li><p>Cleaning the solution and the whole project.</p></li>
  </ol>