diff --git a/app/build.gradle b/app/build.gradle
index bfdaff3..bfd416f 100644
--- a/app/build.gradle
+++ b/app/build.gradle
@@ -31,6 +31,29 @@ android {
             minifyEnabled false
             proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
         }
+
+        applicationVariants.all{
+            variant ->
+                variant.outputs.each{
+                    output->
+                        // on below line we are specifying our app name.
+                        project.ext { appName = 'kirbyTestApp' }
+                        // on below line we are adding the formatted date to our apk file name.
+                        def formattedDate = new Date().format('yyyyMMdd')
+                        // on below line we are creating a new name for our apk.
+                        def newName = output.outputFile.name
+                        // on below line we are replacing our previous name with our app name.
+                        newName = newName.replace("app-", "$project.ext.appName-")
+                        // 當build type為 debug時觸發
+                        // on below line we are replacing -debug with our formatted date.
+                        newName = newName.replace("-debug", "-debug-" + formattedDate)
+                        // 當build type為 release時觸發
+                        // on below line we are replacing -release with our formatted date.
+                        newName = newName.replace("-release", "-release-" + formattedDate)
+                        // at last we are setting our apk name to it.
+                        output.outputFileName  = newName
+                }
+        }
     }
     compileOptions {
         sourceCompatibility JavaVersion.VERSION_1_8