prepare a Release mode

app/build.gradle

@@ -1,9 +1,16 @@
 apply plugin: 'com.android.application'
 
 android {
+    signingConfigs {
+        config {
+            keyAlias RELEASE_KEY_ALIAS
+            keyPassword RELEASE_KEY_PASSWORD
+            storeFile file('../release.keystore')
+            storePassword RELEASE_STORE_PASSWORD
+        }
+    }
     compileSdkVersion 23
     buildToolsVersion "23.0.2"
-
     defaultConfig {
         applicationId "flashlight.simplemobiletools.com"
         minSdkVersion 16
@@ -13,8 +20,9 @@ android {
     }
     buildTypes {
         release {
-            minifyEnabled false
+            minifyEnabled true
             proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
+            signingConfig signingConfigs.config
         }
     }
 }