Default proguard rules template based on the following blog posts, http://omgitsmgp.com/2013/09/09/a-conservative-guide-to-proguard-for-android/ and http://www.crashlytics.com/blog/mastering-proguard-for-building-lightweight-android-code/

proguard-rules-template.pro

# Add project specific ProGuard rules here.
# By default, the flags in this file are appended to flags specified
# in F:\1.Local_Docs\2.AndroidSDK\sdk/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 *;
#}

#standard proguard excludes based on this article >  http://omgitsmgp.com/2013/09/09/a-conservative-guide-to-proguard-for-android/

-keep public class * extends android.app.Activity
-keep public class * extends android.app.Application
-keep public class * extends android.app.Service
-keep public class * extends android.content.BroadcastReceiver
-keep public class * extends android.content.ContentProvider
-keep public class * extends android.preference.Preference
-keep public class com.android.vending.billing.IInAppBillingService
-keep public class * extends android.view.View {
    public <init>(android.content.Context);
    public <init>(android.content.Context, android.util.AttributeSet);
    public <init>(android.content.Context, android.util.AttributeSet, int);
}
-keepclasseswithmembers class * {
    public <init>(android.content.Context, android.util.AttributeSet);
}
-keepclasseswithmembers class * {
    public <init>(android.content.Context, android.util.AttributeSet, int);
}
-keepclassmembers class * extends android.content.Context {
    public void *(android.view.View);
    public void *(android.view.MenuItem);
}

# exclude library projects that have already probably be proguarded
# from this article > http://www.crashlytics.com/blog/mastering-proguard-for-building-lightweight-android-code/

-libraryjars libs
-keep class com.crashlytics.** { *; }
# add other libary packages here....
# support libs too...
-keep class android.support.v4.app.** { *; }
-keep interface android.support.v4.app.** { *; }

# print mappings for analytics

-printseeds seeds.txt
-printusage unused.txt
-printmapping mapping.txt