title: React Native signed release builds but fails to start
body: <p>I am trying to run my react native app in release mode.
  The APK is signed per documentation and it worked fine the first times (both in the emulator and in a real device).</p>
  
  <p>After some updates though ( adding libraries, changing the gradle config, developing more code) the release install does not work anymore:</p>
  
  <ul>
  <li>In debug mode all works OK (build, emulator and real phone)</li>
  <li>In release mode builds OK but app crashes at start (emulator and real phone)</li>
  </ul>
  
  <p>In the logs I see the following error:</p>
  
  <pre><code>adb logcat
  
  ....
  Unable to instantiate application com.myfakeappname.MainApplication: java.lang.ClassNotFoundException: Didn't find class "com.myfakeappname.MainApplication" on path: DexPathList...
  ....
  </code></pre>
  
  <p>Here's my AndroidManifest.xml under the release folder</p>
  
  <pre><code>&lt;manifest xmlns:android="http://schemas.android.com/apk/res/android"
        xmlns:tools="http://schemas.android.com/tools"
        package="com.myfakeappname"&gt;
  
        &lt;application
          android:name=".MainApplication"
          &gt;
  
        &lt;/application&gt;
   &lt;/manifest&gt;
  </code></pre>
  
  <p>EDIT: adding proguard-rules.pro</p>
  
  <pre><code># Add project specific ProGuard rules here.
  # By default, the flags in this file are appended to flags specified
  # in /usr/local/Cellar/android-sdk/24.3.3/tools/proguard/proguard-android.txt
  # You can edit the include path and order by changing the proguardFiles
  # directive in build.gradle.
  #
  # For more details, see
  #   http://developer.android.com/guide/developing/tools/proguard.html
  
  # Add any project specific keep options here:
  
  # If your project uses WebView with JS, uncomment the following
  # and specify the fully qualified class name to the JavaScript interface
  # class:
  #-keepclassmembers class fqcn.of.javascript.interface.for.webview {
  #   public *;
  #}
  
  # Disabling obfuscation is useful if you collect stack traces from production crashes
  # (unless you are using a system that supports de-obfuscate the stack traces).
  -dontobfuscate
  
  # React Native
  
  # Keep our interfaces so they can be used by other ProGuard rules.
  # See http://sourceforge.net/p/proguard/bugs/466/
  -keep,allowobfuscation @interface com.facebook.proguard.annotations.DoNotStrip
  -keep,allowobfuscation @interface com.facebook.proguard.annotations.KeepGettersAndSetters
  -keep,allowobfuscation @interface com.facebook.common.internal.DoNotStrip
  
  # Do not strip any method/class that is annotated with @DoNotStrip
  -keep @com.facebook.proguard.annotations.DoNotStrip class *
  -keep @com.facebook.common.internal.DoNotStrip class *
  -keepclassmembers class * {
      @com.facebook.proguard.annotations.DoNotStrip *;
      @com.facebook.common.internal.DoNotStrip *;
  }
  
  -keepclassmembers @com.facebook.proguard.annotations.KeepGettersAndSetters class * {
    void set*(***);
    *** get*();
  }
  
  -keep class * extends com.facebook.react.bridge.JavaScriptModule { *; }
  -keep class * extends com.facebook.react.bridge.NativeModule { *; }
  -keepclassmembers,includedescriptorclasses class * { native &lt;methods&gt;; }
  -keepclassmembers class *  { @com.facebook.react.uimanager.UIProp &lt;fields&gt;; }
  -keepclassmembers class *  { @com.facebook.react.uimanager.annotations.ReactProp &lt;methods&gt;; }
  -keepclassmembers class *  { @com.facebook.react.uimanager.annotations.ReactPropGroup &lt;methods&gt;; }
  
  -dontwarn com.facebook.react.**
  
  # okhttp
  
  -keepattributes Signature
  -keepattributes *Annotation*
  -keep class okhttp3.** { *; }
  -keep interface okhttp3.** { *; }
  -dontwarn okhttp3.**
  
  # okio
  
  -keep class sun.misc.Unsafe { *; }
  -dontwarn java.nio.file.*
  -dontwarn org.codehaus.mojo.animal_sniffer.IgnoreJRERequirement
  -dontwarn okio.**
  </code></pre>