diff --git a/app/build.gradle b/app/build.gradle
index 443b7c79..2a633f71 100644
--- a/app/build.gradle
+++ b/app/build.gradle
@@ -18,10 +18,12 @@ android {
 
     signingConfigs {
         release {
-            storeFile file(localProperties['KEYSTORE_FILE'])
-            storePassword localProperties['KEYSTORE_PASSWORD']
-            keyAlias localProperties['KEY_ALIAS']
-            keyPassword localProperties['KEY_PASSWORD']
+            if (localProperties['KEYSTORE_FILE']) {
+                storeFile file(localProperties['KEYSTORE_FILE'])
+                storePassword localProperties['KEYSTORE_PASSWORD']
+                keyAlias localProperties['KEY_ALIAS']
+                keyPassword localProperties['KEY_PASSWORD']
+            }
         }
     }
 
@@ -49,11 +51,18 @@ android {
 
     buildTypes {
         release {
-            signingConfig signingConfigs.release
+            if (signingConfigs.release.storeFile) {
+                signingConfig signingConfigs.release
+            }
             minifyEnabled true
             shrinkResources true
             proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
         }
+        releaseUnsigned {
+            initWith release
+            signingConfig null
+            matchingFallbacks = ['release']
+        }
     }
     compileOptions {
         sourceCompatibility = JavaVersion.VERSION_17
@@ -83,6 +92,11 @@ android {
                     output.outputFileName = "app-${abi}-${variant.buildType.name}.apk"
                 }
             }
+
+            // Override name specifically for releaseUnsigned
+            if (variant.buildType.name == "releaseUnsigned") {
+                output.outputFileName = "app-release-unsigned.apk"
+            }
         }
     }
 
diff --git a/app/src/main/AndroidManifest.xml b/app/src/main/AndroidManifest.xml
index fc9c66d2..5ff4b7f9 100644
--- a/app/src/main/AndroidManifest.xml
+++ b/app/src/main/AndroidManifest.xml
@@ -28,12 +28,18 @@
         <activity
             android:name=".setting_activity.MainActivity"
             android:exported="true"
+            android:label="@string/title_activity_main" />
+
+        <activity-alias
+            android:name=".setting_activity.LaunchableMainActivity"
+            android:targetActivity=".setting_activity.MainActivity"
+            android:exported="true"
             android:label="@string/title_activity_main">
             <intent-filter>
                 <action android:name="android.intent.action.MAIN" />
                 <category android:name="android.intent.category.LAUNCHER" />
             </intent-filter>
-        </activity>
+        </activity-alias>
 
         <service
             android:name=".ime_service.IMEService"