diff --git a/app/build.gradle.kts b/app/build.gradle.kts
index 64997382..be9072e8 100644
--- a/app/build.gradle.kts
+++ b/app/build.gradle.kts
@@ -37,8 +37,8 @@ android {
         applicationId = "org.kabiri.android.usbterminal"
         minSdk = 24
         targetSdk = 35
-        versionCode = System.getenv("CIRCLE_BUILD_NUM")?.toIntOrNull() ?: 16
-        versionName = "0.9.86${System.getenv("CIRCLE_BUILD_NUM") ?: ""}"
+        versionCode = System.getenv("CIRCLE_BUILD_NUM")?.toIntOrNull() ?: 17
+        versionName = "0.9.87${System.getenv("CIRCLE_BUILD_NUM") ?: ""}"
         testInstrumentationRunner = "androidx.test.runner.AndroidJUnitRunner"
     }
 
diff --git a/app/src/main/AndroidManifest.xml b/app/src/main/AndroidManifest.xml
index 07074fa9..5f3634f6 100644
--- a/app/src/main/AndroidManifest.xml
+++ b/app/src/main/AndroidManifest.xml
@@ -15,7 +15,7 @@
         android:label="@string/app_name"
         android:roundIcon="@mipmap/ic_launcher_round"
         android:supportsRtl="true"
-        android:theme="@style/AppTheme"
+        android:theme="@style/UsbTerminalTheme"
         android:dataExtractionRules="@xml/data_extraction_rules"
         tools:targetApi="s">
 
diff --git a/app/src/main/java/org/kabiri/android/usbterminal/MainActivity.kt b/app/src/main/java/org/kabiri/android/usbterminal/MainActivity.kt
index c722126a..aea72c65 100644
--- a/app/src/main/java/org/kabiri/android/usbterminal/MainActivity.kt
+++ b/app/src/main/java/org/kabiri/android/usbterminal/MainActivity.kt
@@ -36,11 +36,21 @@ class MainActivity : AppCompatActivity() {
         viewModel.startObservingUsbDevice()
         setContentView(R.layout.activity_main)
 
-        // avoid system navbar or soft keyboard overlapping the content.
         val rootView = findViewById<View>(R.id.root_view)
+        val toolbar = findViewById<com.google.android.material.appbar.MaterialToolbar>(R.id.toolbar)
+        setSupportActionBar(toolbar)
+
         ViewCompat.setOnApplyWindowInsetsListener(rootView) { view, insets ->
             val systemBarsInsets = insets.getInsets(WindowInsetsCompat.Type.systemBars())
             val imeInsets = insets.getInsets(WindowInsetsCompat.Type.ime())
+
+            // Toolbar consumes status bar space; content avoids bottom system bars
+            toolbar.setPadding(
+                toolbar.paddingLeft,
+                systemBarsInsets.top,
+                toolbar.paddingRight,
+                toolbar.paddingBottom,
+            )
             view.setPadding(0, 0, 0, maxOf(systemBarsInsets.bottom, imeInsets.bottom))
             insets
         }
diff --git a/app/src/main/java/org/kabiri/android/usbterminal/ui/common/CustomBottomSheetDialogFragment.kt b/app/src/main/java/org/kabiri/android/usbterminal/ui/common/CustomBottomSheetDialogFragment.kt
index 5b914562..d2483304 100644
--- a/app/src/main/java/org/kabiri/android/usbterminal/ui/common/CustomBottomSheetDialogFragment.kt
+++ b/app/src/main/java/org/kabiri/android/usbterminal/ui/common/CustomBottomSheetDialogFragment.kt
@@ -12,7 +12,7 @@ open class CustomBottomSheetDialogFragment(
     private val canUserDragToCancel: Boolean = true,
 ): BottomSheetDialogFragment() {
 
-    override fun getTheme(): Int = R.style.ModalBottomSheetTheme
+    override fun getTheme(): Int = R.style.SettingModalBottomSheetTheme
 
     override fun onCreateDialog(savedInstanceState: Bundle?): Dialog =
         BottomSheetDialog(requireContext(), theme)
diff --git a/app/src/main/res/layout/activity_main.xml b/app/src/main/res/layout/activity_main.xml
index 0c64f181..e2b6c922 100644
--- a/app/src/main/res/layout/activity_main.xml
+++ b/app/src/main/res/layout/activity_main.xml
@@ -8,6 +8,26 @@
     android:layout_height="match_parent"
     tools:context=".MainActivity">
 
+    <com.google.android.material.appbar.AppBarLayout
+        android:id="@+id/app_bar"
+        android:layout_width="0dp"
+        android:layout_height="wrap_content"
+        android:background="?attr/colorPrimary"
+        app:layout_constraintTop_toTopOf="parent"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintEnd_toEndOf="parent">
+
+        <com.google.android.material.appbar.MaterialToolbar
+            android:id="@+id/toolbar"
+            style="@style/Widget.MaterialComponents.Toolbar"
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:background="?attr/colorPrimary"
+            app:titleTextColor="@android:color/white"
+            app:navigationIconTint="@android:color/white" />
+
+    </com.google.android.material.appbar.AppBarLayout>
+
     <TextView
         android:id="@+id/tvOutput"
         android:layout_width="0dp"
@@ -22,7 +42,7 @@
         app:layout_constraintLeft_toLeftOf="parent"
         app:layout_constraintRight_toRightOf="parent"
         app:layout_constraintStart_toStartOf="parent"
-        app:layout_constraintTop_toTopOf="parent" />
+        app:layout_constraintTop_toBottomOf="@id/app_bar" />
 
     <Button
         android:id="@+id/btEnter"
@@ -49,4 +69,4 @@
         app:layout_constraintStart_toStartOf="parent"
         android:imeOptions="actionSend"/>
 
-</androidx.constraintlayout.widget.ConstraintLayout>
\ No newline at end of file
+</androidx.constraintlayout.widget.ConstraintLayout>
diff --git a/app/src/main/res/values-night/styles.xml b/app/src/main/res/values-night/styles.xml
new file mode 100644
index 00000000..7cf31cdb
--- /dev/null
+++ b/app/src/main/res/values-night/styles.xml
@@ -0,0 +1,6 @@
+<resources xmlns:tools="http://schemas.android.com/tools">
+    <!-- Night: nav bar icons should be light -->
+    <style name="SettingModalBottomSheetTheme" parent="@style/ModalBottomSheetTheme.Base">
+        <item name="android:windowLightNavigationBar" tools:targetApi="27">false</item>
+    </style>
+</resources>
diff --git a/app/src/main/res/values-v23/styles.xml b/app/src/main/res/values-v23/styles.xml
new file mode 100644
index 00000000..4a3b75b9
--- /dev/null
+++ b/app/src/main/res/values-v23/styles.xml
@@ -0,0 +1,12 @@
+<resources>
+    <!-- API 23+: control status bar icon contrast (dark icons vs light icons) -->
+    <style name="UsbTerminalTheme" parent="@style/AppTheme.Base">
+        <!-- Turquoise status bar needs light icons for readability -->
+        <item name="android:windowLightStatusBar">false</item>
+    </style>
+
+    <style name="SettingModalBottomSheetTheme" parent="@style/ModalBottomSheetTheme.Base">
+        <!-- Keep light icons on the turquoise status bar in the modal as well -->
+        <item name="android:windowLightStatusBar">false</item>
+    </style>
+</resources>
diff --git a/app/src/main/res/values-v29/styles.xml b/app/src/main/res/values-v29/styles.xml
new file mode 100644
index 00000000..9921f364
--- /dev/null
+++ b/app/src/main/res/values-v29/styles.xml
@@ -0,0 +1,12 @@
+<resources>
+    <!-- API 29+: disable forced contrast scrims on system bars -->
+    <style name="UsbTerminalTheme" parent="@style/AppTheme.Base">
+        <item name="android:enforceStatusBarContrast">false</item>
+        <item name="android:enforceNavigationBarContrast">false</item>
+    </style>
+
+    <style name="SettingModalBottomSheetTheme" parent="@style/ModalBottomSheetTheme.Base">
+        <item name="android:enforceStatusBarContrast">false</item>
+        <item name="android:enforceNavigationBarContrast">false</item>
+    </style>
+</resources>
diff --git a/app/src/main/res/values/styles.xml b/app/src/main/res/values/styles.xml
index 2fb7bc72..fda2dc1b 100644
--- a/app/src/main/res/values/styles.xml
+++ b/app/src/main/res/values/styles.xml
@@ -1,25 +1,30 @@
 <resources xmlns:tools="http://schemas.android.com/tools">
 
     <!-- Base application theme. -->
-    <style name="AppTheme" parent="Theme.AppCompat.DayNight.DarkActionBar">
+    <style name="AppTheme.Base" parent="Theme.Material3.DayNight.NoActionBar">
         <!-- Customize your theme here. -->
         <item name="colorPrimary">@color/colorPrimary</item>
-        <item name="colorPrimaryDark">@color/colorPrimaryDark</item>
+        <!-- Ensure status bar tone matches app bar exactly -->
+        <item name="colorPrimaryDark">@color/colorPrimary</item>
         <item name="colorAccent">@color/colorAccent</item>
 
         <item name="android:textColorPrimary">@color/textColorPrimary</item>
         <item name="android:textColorSecondary">@color/textColorSecondary</item>
     </style>
 
-    <style name="ModalBottomSheet" parent="@style/Widget.Design.BottomSheet.Modal">
-        <item name="android:background">@drawable/bg_modal_bottom_sheet</item>
+    <!-- App theme alias; v23 will override this to add icon contrast -->
+    <style name="UsbTerminalTheme" parent="@style/AppTheme.Base" />
+
+    <!-- Common items for the bottom sheet theme -->
+    <style name="ModalBottomSheetTheme.Base" parent="Theme.Material3.DayNight.BottomSheetDialog">
+        <!-- Edge-to-edge for modal as well; host handles coloring -->
+        <item name="android:navigationBarColor">@color/bg_modal_bottom_sheet</item>
+        <item name="android:windowDrawsSystemBarBackgrounds">true</item>
     </style>
 
-    <style name="ModalBottomSheetTheme" parent="Theme.Design.BottomSheetDialog">
-        <item name="android:statusBarColor">@android:color/transparent</item>
+    <!-- Day variant adds light nav bar icons -->
+    <style name="SettingModalBottomSheetTheme" parent="@style/ModalBottomSheetTheme.Base">
         <item name="android:windowLightNavigationBar" tools:targetApi="27">true</item>
-        <item name="android:windowIsFloating">false</item>
-        <item name="bottomSheetStyle">@style/ModalBottomSheet</item>
     </style>
 
 </resources>