How to reduce Android Apk size
<p>I am developing application which contains below dependency </p>

<p>Module level</p>

<pre><code>dependencies {
compile fileTree(include: ['*.jar'], dir: 'libs')
testCompile 'junit:junit:4.12'
compile 'com.android.support:appcompat-v7:23.3.0'
compile 'com.android.support:design:23.3.0'
compile 'com.google.android.gms:play-services:9.0.0' **// for GCM**
compile 'com.android.support:cardview-v7:23.3.0'
compile 'com.squareup.picasso:picasso:2.5.2' **//Rounding and displaying image from URL**
compile 'com.google.code.gson:gson:2.6.2'
compile 'com.github.lecho:hellocharts-library:1.5.8@aar' **// For bar graph** 
compile('com.crashlytics.sdk.android:crashlytics:2.5.5@aar') {
    transitive = true;
}
compile 'com.google.firebase:firebase-core:9.0.0' **// Analytics**
</code></pre>

<p>}</p>

<p>Project level</p>

<pre><code>dependencies {
    classpath 'com.android.tools.build:gradle:2.1.2'
    classpath 'com.google.gms:google-services:3.0.0'
    classpath 'io.realm:realm-gradle-plugin:1.0.1' // Database
    // NOTE: Do not place your application dependencies here; they belong
    // in the individual module build.gradle files
}
</code></pre>

<p>my </p>

<p>/Assets /150kb using font aweasome file. </p>

<p>/java - 644 KB</p>

<p>/res - 740 KB (used high resolution image 1920*1280 size 220kb compress with tinypng)</p>

<p>Already applied ProGuard. 
delete unused file and codes.</p>

<p><strong>Question</strong></p>

<p>Still my app size is 7.03MB </p>

<p>How can i reduce app size? i don't know why this is 7.03MB </p>

<p>Is there any calculation which give size that used by dependency in apk?</p>

<p>Like google play service occupied around 200kb in apk. </p>