title: Android Studio UNEXPECTED TOP-LEVEL EXCEPTION
body: <p>I just created a build for my up, after changing from one branch to another I got this error which is a little bit tricky to solve.</p>
  
  <p>here is the error. Thanks in advance</p>
  
  <p>Error:Execution failed for task ':app-ayosdito:dexDebug'.</p>
  
  <blockquote>
    <p>com.android.ide.common.internal.LoggedErrorException: Failed to run command:
        /home/rego/Documents/Dev/android-studio/sdk/build-tools/20.0.0/dx --dex --num-threads=4 --output /home/rego/Documents/repo/android_as/android-ayosdito-master/app-ayosdito/build/intermediates/dex/debug /home/rego/Documents/repo/android_as/android-ayosdito-master/app-ayosdito/build/intermediates/classes/debug /home/rego/Documents/repo/android_as/android-ayosdito-master/app-ayosdito/build/intermediates/dependency-cache/debug /home/rego/Documents/repo/android_as/android-ayosdito-master/app-ayosdito/build/intermediates/pre-dexed/debug/classes-935aff4a1ad7b57ba9deddb2d9234268efd49e8b.jar /home/rego/Documents/repo/android_as/android-ayosdito-master/app-ayosdito/build/intermediates/pre-dexed/debug/bolts-5a50c10fe3e919e7fb041f9b10cb65e1b32ba1eb.jar /home/rego/Documents/repo/android_as/android-ayosdito-master/app-ayosdito/build/intermediates/pre-dexed/debug/crashlytics-611bad234c2a1e97a924d7e38bcfa13ac1570355.jar /home/rego/Documents/repo/android_as/android-ayosdito-master/app-ayosdito/build/intermediates/pre-dexed/debug/support-annotations-20.0.0-bc6619c8f24fa3fd370760fc86d408d312f05ec2.jar /home/rego/Documents/repo/android_as/android-ayosdito-master/app-ayosdito/build/intermediates/pre-dexed/debug/commons-io-2.4-caec15b81917fb6acd3298650cc00c30e17eede0.jar /home/rego/Documents/repo/android_as/android-ayosdito-master/app-ayosdito/build/intermediates/pre-dexed/debug/classes-12ad7b05a4f0fe39486e3025281eaeddcef91198.jar /home/rego/Documents/repo/android_as/android-ayosdito-master/app-ayosdito/build/intermediates/pre-dexed/debug/classes-00278ef4b16e16c05cb6b5b080df200e551a1882.jar /home/rego/Documents/repo/android_as/android-ayosdito-master/app-ayosdito/build/intermediates/pre-dexed/debug/picasso-2.2-6fafbbf8556c6c3ba3405a6ac47a14025112bb8b.jar /home/rego/Documents/repo/android_as/android-ayosdito-master/app-ayosdito/build/intermediates/pre-dexed/debug/crashlytics-1.1.13-70edec0dfae55592b9adda0d3a85a269f12d1c89.jar /home/rego/Documents/repo/android_as/android-ayosdito-master/app-ayosdito/build/intermediates/pre-dexed/debug/nineold-library-bea06224997ec3fd30178fb3665d65ca4e30e5f5.jar /home/rego/Documents/repo/android_as/android-ayosdito-master/app-ayosdito/build/intermediates/pre-dexed/debug/classes-6b3efcc0c6fa1a6f8e8fafc4356f986843a9b2e0.jar /home/rego/Documents/repo/android_as/android-ayosdito-master/app-ayosdito/build/intermediates/pre-dexed/debug/sanselan1-9299255fb0fdca9a978694b543f3dcba073c7ea2.jar /home/rego/Documents/repo/android_as/android-ayosdito-master/app-ayosdito/build/intermediates/pre-dexed/debug/classes-87614b3d145403f26927454e3d424ae8b00253ca.jar /home/rego/Documents/repo/android_as/android-ayosdito-master/app-ayosdito/build/intermediates/pre-dexed/debug/internal_impl-20.0.0-26a5807e5e8224af51a878c0b41529d250af0a76.jar /home/rego/Documents/repo/android_as/android-ayosdito-master/app-ayosdito/build/intermediates/pre-dexed/debug/ATInternet-47f9743da3d5dd9debd122ec95974647bd45262a.jar /home/rego/Documents/repo/android_as/android-ayosdito-master/app-ayosdito/build/intermediates/pre-dexed/debug/classes-15b07969dcbf9d645a3a6ca48de777b7f14233de.jar /home/rego/Documents/repo/android_as/android-ayosdito-master/app-ayosdito/build/intermediates/pre-dexed/debug/httpmime-4.1-beta1-57575d1be0c64df2c59ddf9c5e31f087cb44dc05.jar
      Error Code:
        2
      Output:
        UNEXPECTED TOP-LEVEL EXCEPTION:
        com.android.dex.DexException: Multiple dex files define Lcom/crashlytics/android/A;
            at com.android.dx.merge.DexMerger.readSortableTypes(DexMerger.java:594)
            at com.android.dx.merge.DexMerger.getSortedTypes(DexMerger.java:552)
            at com.android.dx.merge.DexMerger.mergeClassDefs(DexMerger.java:533)
            at com.android.dx.merge.DexMerger.mergeDexes(DexMerger.java:170)
            at com.android.dx.merge.DexMerger.merge(DexMerger.java:188)
            at com.android.dx.command.dexer.Main.mergeLibraryDexBuffers(Main.java:439)
            at com.android.dx.command.dexer.Main.runMonoDex(Main.java:287)
            at com.android.dx.command.dexer.Main.run(Main.java:230)
            at com.android.dx.command.dexer.Main.main(Main.java:199)
            at com.android.dx.command.Main.main(Main.java:103)</p>
  </blockquote>