diff --git a/WearOS/Wearable/build.gradle b/WearOS/Wearable/build.gradle
index 22166432..5eccd232 100644
--- a/WearOS/Wearable/build.gradle
+++ b/WearOS/Wearable/build.gradle
@@ -21,12 +21,12 @@ plugins {
 apply plugin: 'kotlin-android'
 
 android {
-    compileSdkVersion 30
+    compileSdkVersion 31
 
     defaultConfig {
         applicationId "com.example.wearos"
         minSdkVersion 23
-        targetSdkVersion 30
+        targetSdkVersion 31
         versionCode 1
         versionName "1.0"
     }
diff --git a/WearOS/Wearable/src/main/AndroidManifest.xml b/WearOS/Wearable/src/main/AndroidManifest.xml
index 8465d4ac..4c24df10 100644
--- a/WearOS/Wearable/src/main/AndroidManifest.xml
+++ b/WearOS/Wearable/src/main/AndroidManifest.xml
@@ -39,7 +39,8 @@
 
         <activity
             android:name=".kt.MainActivity"
-            android:label="@string/app_name" >
+            android:label="@string/app_name"
+            android:exported="true" >
 
             <intent-filter>
                 <action android:name="android.intent.action.MAIN" />
diff --git a/tutorials/java/Polygons/app/src/main/java/com/example/polygons/PolyActivity.java b/tutorials/java/Polygons/app/src/main/java/com/example/polygons/PolyActivity.java
index 724d20db..740b2e56 100644
--- a/tutorials/java/Polygons/app/src/main/java/com/example/polygons/PolyActivity.java
+++ b/tutorials/java/Polygons/app/src/main/java/com/example/polygons/PolyActivity.java
@@ -224,10 +224,10 @@ public class PolyActivity extends AppCompatActivity
 
     // [START maps_poly_activity_style_polygon]
     private static final int COLOR_WHITE_ARGB = 0xffffffff;
-    private static final int COLOR_GREEN_ARGB = 0xff388E3C;
-    private static final int COLOR_PURPLE_ARGB = 0xff81C784;
-    private static final int COLOR_ORANGE_ARGB = 0xffF57F17;
-    private static final int COLOR_BLUE_ARGB = 0xffF9A825;
+    private static final int COLOR_DARK_GREEN_ARGB = 0xff388E3C;
+    private static final int COLOR_LIGHT_GREEN_ARGB = 0xff81C784;
+    private static final int COLOR_DARK_ORANGE_ARGB = 0xffF57F17;
+    private static final int COLOR_LIGHT_ORANGE_ARGB = 0xffF9A825;
 
     private static final int POLYGON_STROKE_WIDTH_PX = 8;
     private static final int PATTERN_DASH_LENGTH_PX = 20;
@@ -260,14 +260,14 @@ public class PolyActivity extends AppCompatActivity
             case "alpha":
                 // Apply a stroke pattern to render a dashed line, and define colors.
                 pattern = PATTERN_POLYGON_ALPHA;
-                strokeColor = COLOR_GREEN_ARGB;
-                fillColor = COLOR_PURPLE_ARGB;
+                strokeColor = COLOR_DARK_GREEN_ARGB;
+                fillColor = COLOR_LIGHT_GREEN_ARGB;
                 break;
             case "beta":
                 // Apply a stroke pattern to render a line of dots and dashes, and define colors.
                 pattern = PATTERN_POLYGON_BETA;
-                strokeColor = COLOR_ORANGE_ARGB;
-                fillColor = COLOR_BLUE_ARGB;
+                strokeColor = COLOR_DARK_ORANGE_ARGB;
+                fillColor = COLOR_LIGHT_ORANGE_ARGB;
                 break;
         }
 
diff --git a/tutorials/kotlin/Polygons/app/src/main/java/com/example/polygons/PolyActivity.kt b/tutorials/kotlin/Polygons/app/src/main/java/com/example/polygons/PolyActivity.kt
index fc0c332c..51f4389e 100644
--- a/tutorials/kotlin/Polygons/app/src/main/java/com/example/polygons/PolyActivity.kt
+++ b/tutorials/kotlin/Polygons/app/src/main/java/com/example/polygons/PolyActivity.kt
@@ -205,10 +205,10 @@ class PolyActivity : AppCompatActivity(), OnMapReadyCallback, OnPolylineClickLis
 
     // [START maps_poly_activity_style_polygon]
     private val COLOR_WHITE_ARGB = -0x1
-    private val COLOR_GREEN_ARGB = -0xc771c4
-    private val COLOR_PURPLE_ARGB = -0x7e387c
-    private val COLOR_ORANGE_ARGB = -0xa80e9
-    private val COLOR_BLUE_ARGB = -0x657db
+    private val COLOR_DARK_GREEN_ARGB = -0xc771c4
+    private val COLOR_LIGHT_GREEN_ARGB = -0x7e387c
+    private val COLOR_DARK_ORANGE_ARGB = -0xa80e9
+    private val COLOR_LIGHT_ORANGE_ARGB = -0x657db
     private val POLYGON_STROKE_WIDTH_PX = 8
     private val PATTERN_DASH_LENGTH_PX = 20
 
@@ -234,14 +234,14 @@ class PolyActivity : AppCompatActivity(), OnMapReadyCallback, OnPolylineClickLis
             "alpha" -> {
                 // Apply a stroke pattern to render a dashed line, and define colors.
                 pattern = PATTERN_POLYGON_ALPHA
-                strokeColor = COLOR_GREEN_ARGB
-                fillColor = COLOR_PURPLE_ARGB
+                strokeColor = COLOR_DARK_GREEN_ARGB
+                fillColor = COLOR_LIGHT_GREEN_ARGB
             }
             "beta" -> {
                 // Apply a stroke pattern to render a line of dots and dashes, and define colors.
                 pattern = PATTERN_POLYGON_BETA
-                strokeColor = COLOR_ORANGE_ARGB
-                fillColor = COLOR_BLUE_ARGB
+                strokeColor = COLOR_DARK_ORANGE_ARGB
+                fillColor = COLOR_LIGHT_ORANGE_ARGB
             }
         }
         polygon.strokePattern = pattern