Android : AWS Android SDK+AppCompat V7 incompatability[Android Studio]

In an existing application I tried including AWS S3, Core and Cognito jars [downloaded from AWS] in libs folder and added the commands in build.gradle. But trouble started with 'Top Level Exception'. I included the necessary changes for multipleDex and over 65k limit. Now the new problem is that build goes fine and apk is generated but it just fails to start [as I access v7 compat theme bar elements upon start]. I get classdefnotfound error for UI elements. I even tried maven repository based approach to include AWS jars - no luck!

Upon some trial and error - I have narrowed down the problem area. S3 and Cognito JARs are not the culprits but core JAR seems to cause problem the momement I include it in gradle file. I tried to find internal dependencies thru' gradle tasks but that didn't retun results either.

Here is the gradle file:

buildscript {
    repositories {
        maven { url 'https://maven.fabric.io/public' }
    }

    dependencies {
        classpath 'io.fabric.tools:gradle:1.15.2'
    }
}
apply plugin: 'com.android.application'
apply plugin: 'io.fabric'

repositories {
    mavenCentral()
    maven { url 'https://maven.fabric.io/public' }
    maven {
        url 'https://raw.github.com/embarkmobile/zxing-android-minimal/mvn-repo/maven-repository/'
    }
}

dependencies {
    //compile fileTree(dir: 'libs', include: '*.jar')
    compile 'com.android.support:multidex:1.0.0'
    compile 'com.android.support:appcompat-v7:22.0.0'
    compile project(':sugar-library')
    compile 'com.google.android.gms:play-services:6.5.87'
    compile 'org.apache.httpcomponents:httpmime:4.3.6'
    compile 'org.apache.httpcomponents:httpcore:4.3.3'
    compile 'com.path:android-priority-jobqueue:1.1.2'
    compile 'de.greenrobot:eventbus:2.4.0'
    compile 'com.melnykov:floatingactionbutton:1.1.0'
    compile 'com.android.support:recyclerview-v7:21.0.3'
    compile 'com.github.nkzawa:socket.io-client:0.3.0'
    compile 'com.facebook.android:facebook-android-sdk:3.21.1'
    compile 'com.google.zxing:core:2.2'
    compile 'com.embarkmobile:zxing-android-minimal:1.2.1@aar'
    compile('com.crashlytics.sdk.android:crashlytics:2.2.1@aar') {
        transitive = true;
    }
    compile 'com.mixpanel.android:mixpanel-android:4.5.3'
    compile 'com.konotor:KonotorActivity:3.0.4'
    compile 'com.amazonaws:aws-android-sdk-core:2.1.3'
    compile 'com.amazonaws:aws-android-sdk-s3:2.1.3'
}



android {
    compileSdkVersion 22
    buildToolsVersion "22"

    dexOptions {
        javaMaxHeapSize "4g"
    }

    defaultConfig {
        applicationId "com.findulum.smartpocketapp"
        minSdkVersion 14
        targetSdkVersion 22
        versionName "1.0.25"
        versionCode 35
        multiDexEnabled true
    }

    packagingOptions {
        exclude 'META-INF/DEPENDENCIES'
        exclude 'META-INF/NOTICE'
        exclude 'META-INF/LICENSE'
    }

    lintOptions {
        abortOnError false
    }

    sourceSets {
        main {
            manifest.srcFile 'AndroidManifest.xml'
            java.srcDirs = ['src']
            resources.srcDirs = ['src']
            aidl.srcDirs = ['src']
            renderscript.srcDirs = ['src']
            res.srcDirs = ['res']
            assets.srcDirs = ['assets']
        }

        // Move the tests to tests/java, tests/res, etc...
        instrumentTest.setRoot('tests')

        // Move the build types to build-types/<type>
        // For instance, build-types/debug/java, build-types/debug/AndroidManifest.xml, ...
        // This moves them out of them default location under src/<type>/... which would
        // conflict with src/ being used by the main source set.
        // Adding new build types or product flavors should be accompanied
        // by a similar customization.
        debug.setRoot('build-types/debug')
        release.setRoot('build-types/release')
    }
}