diff --git a/android/app/src/main/java/io/github/kichikuou/xsystem35/Launcher.kt b/android/app/src/main/java/io/github/kichikuou/xsystem35/Launcher.kt
index d040cb2..4cafee9 100644
--- a/android/app/src/main/java/io/github/kichikuou/xsystem35/Launcher.kt
+++ b/android/app/src/main/java/io/github/kichikuou/xsystem35/Launcher.kt
@@ -127,6 +127,7 @@ class Launcher private constructor(private val rootDir: File) {
         if (!saveDirFound) {
             File(rootDir, SAVE_DIR).mkdir()
         }
+        observer?.onGameListChange()
     }
 
     private fun createDirForGame(): File {
diff --git a/android/app/src/main/java/io/github/kichikuou/xsystem35/LauncherActivity.kt b/android/app/src/main/java/io/github/kichikuou/xsystem35/LauncherActivity.kt
index e128ff8..8d66738 100644
--- a/android/app/src/main/java/io/github/kichikuou/xsystem35/LauncherActivity.kt
+++ b/android/app/src/main/java/io/github/kichikuou/xsystem35/LauncherActivity.kt
@@ -22,6 +22,7 @@ import android.content.Intent
 import android.net.Uri
 import android.os.Bundle
 import android.provider.OpenableColumns
+import android.text.Html
 import android.util.Log
 import android.view.Menu
 import android.view.MenuItem
@@ -53,6 +54,8 @@ class LauncherActivity : Activity(), LauncherObserver {
 
         onGameListChange()
         val listView = findViewById<ListView>(R.id.list)
+        listView.emptyView = findViewById(R.id.empty)
+        findViewById<TextView>(R.id.usage).text = Html.fromHtml(getString(R.string.usage))
         listView.setOnItemClickListener { _, _, position, _ ->
             onListItemClick(position)
         }
@@ -75,23 +78,15 @@ class LauncherActivity : Activity(), LauncherObserver {
     }
 
     private fun onListItemClick(position: Int) {
-        if (position < launcher.games.size) {
-            startGame(launcher.games[position].path, null)
-        } else {
-            val i = Intent(Intent.ACTION_GET_CONTENT)
-            i.type = CONTENT_TYPE_ZIP
-            startActivityForResult(Intent.createChooser(i, getString(R.string.choose_a_file)), INSTALL_REQUEST)
-        }
+        startGame(launcher.games[position].path, null)
     }
 
     private fun onItemLongClick(position: Int): Boolean {
-        if (position < launcher.games.size) {
-            AlertDialog.Builder(this).setTitle(R.string.uninstall_dialog_title)
-                    .setMessage(getString(R.string.uninstall_dialog_message, launcher.games[position].title))
-                    .setPositiveButton(R.string.ok) {_, _ -> uninstall(position)}
-                    .setNegativeButton(R.string.cancel) {_, _ -> }
-                    .show()
-        }
+        AlertDialog.Builder(this).setTitle(R.string.uninstall_dialog_title)
+                .setMessage(getString(R.string.uninstall_dialog_message, launcher.games[position].title))
+                .setPositiveButton(R.string.ok) {_, _ -> uninstall(position)}
+                .setNegativeButton(R.string.cancel) {_, _ -> }
+                .show()
         return true
     }
 
@@ -102,6 +97,12 @@ class LauncherActivity : Activity(), LauncherObserver {
 
     override fun onOptionsItemSelected(item: MenuItem): Boolean {
         return when (item.itemId) {
+            R.id.install_from_zip -> {
+                val i = Intent(Intent.ACTION_GET_CONTENT)
+                i.type = CONTENT_TYPE_ZIP
+                startActivityForResult(Intent.createChooser(i, getString(R.string.choose_a_file)), INSTALL_REQUEST)
+                true
+            }
             R.id.export_savedata -> {
                 val i = Intent(Intent.ACTION_CREATE_DOCUMENT)
                 i.type = CONTENT_TYPE_ZIP
@@ -116,6 +117,12 @@ class LauncherActivity : Activity(), LauncherObserver {
                                        SAVEDATA_IMPORT_REQUEST)
                 true
             }
+            R.id.help -> {
+                AlertDialog.Builder(this)
+                    .setMessage(Html.fromHtml(getString(R.string.usage)))
+                    .show()
+                true
+            }
             R.id.licenses -> {
                 val intent = Intent(this, LicensesMenuActivity::class.java)
                 startActivity(intent)
@@ -157,7 +164,6 @@ class LauncherActivity : Activity(), LauncherObserver {
 
     override fun onGameListChange() {
         val items = launcher.titles.toMutableList()
-        items.add(getString(R.string.install_from_zip))
         val listView = findViewById<ListView>(R.id.list)
         listView.adapter = ArrayAdapter(this, android.R.layout.simple_list_item_1, items)
     }
diff --git a/android/app/src/main/res/layout/launcher.xml b/android/app/src/main/res/layout/launcher.xml
index 18ef6a0..ad2b3bb 100644
--- a/android/app/src/main/res/layout/launcher.xml
+++ b/android/app/src/main/res/layout/launcher.xml
@@ -6,4 +6,12 @@
     <ListView android:id="@+id/list"
         android:layout_width="match_parent"
         android:layout_height="match_parent" />
+    <ScrollView android:id="@+id/empty"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content">
+        <TextView android:id="@+id/usage"
+            android:layout_width="fill_parent"
+            android:layout_height="wrap_content"
+            android:padding="20dp" />
+    </ScrollView>
 </LinearLayout>
\ No newline at end of file
diff --git a/android/app/src/main/res/menu/launcher_menu.xml b/android/app/src/main/res/menu/launcher_menu.xml
index 194085b..684b112 100644
--- a/android/app/src/main/res/menu/launcher_menu.xml
+++ b/android/app/src/main/res/menu/launcher_menu.xml
@@ -1,11 +1,17 @@
 <?xml version="1.0" encoding="utf-8"?>
 <menu xmlns:android="http://schemas.android.com/apk/res/android">
+    <item
+        android:id="@+id/install_from_zip"
+        android:title="@string/action_install_from_zip" />
     <item
         android:id="@+id/export_savedata"
         android:title="@string/action_export_save_data" />
     <item
         android:id="@+id/import_savedata"
         android:title="@string/action_import_save_data" />
+    <item
+        android:id="@+id/help"
+        android:title="@string/action_help" />
     <item
         android:id="@+id/licenses"
         android:title="@string/action_licenses" />
diff --git a/android/app/src/main/res/values-ja/strings.xml b/android/app/src/main/res/values-ja/strings.xml
index ae22c52..0a9fb42 100644
--- a/android/app/src/main/res/values-ja/strings.xml
+++ b/android/app/src/main/res/values-ja/strings.xml
@@ -2,14 +2,15 @@
 <resources>
     <string name="app_name">xsystem35</string>
     <string name="action_export_save_data">セーブデータをエクスポート</string>
+    <string name="action_help">使い方</string>
     <string name="action_import_save_data">セーブデータをインポート</string>
+    <string name="action_install_from_zip">ZIPからインストール</string>
     <string name="action_licenses">オープンソースライセンス</string>
     <string name="cancel">キャンセル</string>
     <string name="cannot_find_ald">System 3.x のファイル (*.ald) が見つかりません。</string>
     <string name="choose_a_file">ファイルを選択</string>
     <string name="error_dialog_title">エラー</string>
     <string name="install_dialog_title">インストール中…</string>
-    <string name="install_from_zip">ZIP からインストール</string>
     <string name="install_progress">%s を展開中</string>
     <string name="no_data_to_import">ZIP アーカイブ中に save/ フォルダが見つかりません。</string>
     <string name="save_data_export_error">セーブデータのエクスポートに失敗しました。</string>
@@ -19,4 +20,21 @@
     <string name="uninstall_dialog_title">確認</string>
     <string name="unsupported_zip">この形式の ZIP はサポートしていません。</string>
     <string name="zip_extraction_error">ZIP の展開に失敗しました。</string>
+    <string name="usage">
+        <![CDATA[
+            <h1>ゲームのインストール方法</h1>
+            <p>1. PC上で、ゲームのファイルが入ったZIPを用意します。例えば以下のようなファイルを含めます:</p>
+            <div>
+                ・鬼畜王SA.ALD<br>
+                ・鬼畜王GA.ALD<br>
+                ・鬼畜王GB.ALD<br>
+                ・鬼畜王WA.ALD<br>
+                ・02.mp3<br>
+                ・03.mp3<br>
+                ・…<br>
+            </div>
+            <p>2. ZIPファイルを (例えばUSB経由で) PCからデバイスに転送します。</p>
+            <p>3. この画面の右上のメニューボタンをタップして「ZIPからインストール」を選択し、転送したZIPを選びます。</p>
+        ]]>
+    </string>
 </resources>
\ No newline at end of file
diff --git a/android/app/src/main/res/values/strings.xml b/android/app/src/main/res/values/strings.xml
index 9113823..a0bb677 100644
--- a/android/app/src/main/res/values/strings.xml
+++ b/android/app/src/main/res/values/strings.xml
@@ -1,14 +1,15 @@
 <resources>
     <string name="app_name">xsystem35</string>
     <string name="action_export_save_data">Export Save Files</string>
+    <string name="action_help">Help</string>
     <string name="action_import_save_data">Import Save Files</string>
+    <string name="action_install_from_zip">Install from ZIP</string>
     <string name="action_licenses">Open source licenses</string>
     <string name="cancel">Cancel</string>
     <string name="cannot_find_ald">Cannot find System 3.x game files (*.ald).</string>
     <string name="choose_a_file">Choose a file</string>
     <string name="error_dialog_title">Error</string>
     <string name="install_dialog_title">Installing…</string>
-    <string name="install_from_zip">Install from ZIP</string>
     <string name="install_progress">Extracting %s</string>
     <string name="no_data_to_import">No save/ folder in the ZIP archive.</string>
     <string name="ok">OK</string>
@@ -19,4 +20,22 @@
     <string name="uninstall_dialog_title">Confirm</string>
     <string name="unsupported_zip">This type of ZIP is not supported.</string>
     <string name="zip_extraction_error">Failed to extract ZIP.</string>
+    <string name="usage">
+        <![CDATA[
+            <h1>How to install a game</h1>
+            <p>1. On your PC, prepare a ZIP containing the game files. For example, it should contain the following files:</p>
+            <div>
+                * KICHIKUSA.ALD<br>
+                * KICHIKUGA.ALD<br>
+                * KICHIKUGB.ALD<br>
+                * KICHIKUWA.ALD<br>
+                * System39.ain<br>
+                * 02.mp3<br>
+                * 03.mp3<br>
+                * …<br>
+            </div>
+            <p>2. Transfer the ZIP file from your PC to the device (e.g. via USB).</p>
+            <p>3. Tap the menu button at the upper-right of this screen, select &quot;Install from ZIP,&quot; and choose the ZIP you transferred.</p>
+        ]]>
+    </string>
 </resources>