diff --git a/app/src/main/java/com/github/kr328/clash/MainActivity.kt b/app/src/main/java/com/github/kr328/clash/MainActivity.kt
index ea8254cb40..e944aef480 100644
--- a/app/src/main/java/com/github/kr328/clash/MainActivity.kt
+++ b/app/src/main/java/com/github/kr328/clash/MainActivity.kt
@@ -30,6 +30,14 @@ import java.util.concurrent.TimeUnit
 import com.github.kr328.clash.design.R as DesignR
 
 class MainActivity : BaseActivity<MainDesign>() {
+
+    companion object {
+        @Volatile
+        @JvmStatic
+        var pendingExternalRequest: Boolean = false
+            private set
+    }
+
     override suspend fun main() {
         val design = MainDesign(this)
 
@@ -129,13 +137,18 @@ class MainActivity : BaseActivity<MainDesign>() {
 
         try {
             if (vpnRequest != null) {
-                val result = startActivityForResult(
-                    ActivityResultContracts.StartActivityForResult(),
-                    vpnRequest
-                )
-
-                if (result.resultCode == RESULT_OK)
-                    startClashService()
+                pendingExternalRequest = true
+                try {
+                    val result = startActivityForResult(
+                        ActivityResultContracts.StartActivityForResult(),
+                        vpnRequest
+                    )
+
+                    if (result.resultCode == RESULT_OK)
+                        startClashService()
+                } finally {
+                    pendingExternalRequest = false
+                }
             }
         } catch (e: Exception) {
             design?.showToast(DesignR.string.unable_to_start_vpn, ToastDuration.Long)
diff --git a/app/src/main/java/com/github/kr328/clash/MainApplication.kt b/app/src/main/java/com/github/kr328/clash/MainApplication.kt
index 9242d72299..237081db3e 100644
--- a/app/src/main/java/com/github/kr328/clash/MainApplication.kt
+++ b/app/src/main/java/com/github/kr328/clash/MainApplication.kt
@@ -2,12 +2,18 @@ package com.github.kr328.clash
 
 import android.app.Application
 import android.content.Context
+import android.os.Process
 import com.github.kr328.clash.common.Global
 import com.github.kr328.clash.common.compat.currentProcessName
 import com.github.kr328.clash.common.log.Log
+import com.github.kr328.clash.design.store.UiStore
 import com.github.kr328.clash.remote.Remote
 import com.github.kr328.clash.service.util.sendServiceRecreated
+import com.github.kr328.clash.util.ApplicationObserver
 import com.github.kr328.clash.util.clashDir
+import kotlinx.coroutines.Job
+import kotlinx.coroutines.delay
+import kotlinx.coroutines.launch
 import java.io.File
 import java.io.FileOutputStream
 
@@ -29,6 +35,52 @@ class MainApplication : Application() {
         Log.d("Process $processName started")
 
         if (processName == packageName) {
+            // Setup auto destroy UI observer (must register before Remote.launch
+            // so our callback is in the listener list before any visibility event)
+            val uiStore = UiStore(this)
+            var autoDestroyJob: Job? = null
+
+            // 含未保存编辑或正在等待外部结果（文件选择器、VPN 授权等）的 Activity，
+            // 存活时不允许杀 UI 进程
+            val protectedActivities: Set<Class<*>> = setOf(
+                NewProfileActivity::class.java,
+                FilesActivity::class.java,
+                LogcatActivity::class.java,
+                MetaFeatureSettingsActivity::class.java,
+                AccessControlActivity::class.java,
+                OverrideSettingsActivity::class.java,
+                PropertiesActivity::class.java,
+            )
+
+            ApplicationObserver.onVisibleChanged { visible ->
+                autoDestroyJob?.cancel()
+                autoDestroyJob = null
+                if (!visible && uiStore.autoDestroyUI) {
+                    autoDestroyJob = Global.launch {
+                        // 持续监测：有等待回调/编辑中则等待，无保护条件持续 3 秒才杀
+                        var idleMs = 0
+                        while (idleMs < 3000) {
+                            delay(500)
+                            val protectedNow = LogcatService.running ||
+                                ApplicationObserver.createdActivities.any { it.javaClass in protectedActivities } ||
+                                MainActivity.pendingExternalRequest
+                            if (protectedNow) {
+                                idleMs = 0
+                            } else {
+                                idleMs += 500
+                            }
+                        }
+                        Log.d("AutoDestroyUI: Killing UI process to free memory")
+                        try {
+                            File(clashDir, "auto_destroy.log").appendText(
+                                "${java.util.Date()} AutoDestroyUI: Killing UI process\n"
+                            )
+                        } catch (e: Exception) { }
+                        Process.killProcess(Process.myPid())
+                    }
+                }
+            }
+
             Remote.launch()
         } else {
             sendServiceRecreated()
diff --git a/app/src/main/java/com/github/kr328/clash/util/Application.kt b/app/src/main/java/com/github/kr328/clash/util/Application.kt
index 1fb6336781..dfad2c12da 100644
--- a/app/src/main/java/com/github/kr328/clash/util/Application.kt
+++ b/app/src/main/java/com/github/kr328/clash/util/Application.kt
@@ -12,14 +12,16 @@ object ApplicationObserver {
     private val _createdActivities: MutableSet<Activity> = mutableSetOf()
     private val _visibleActivities: MutableSet<Activity> = mutableSetOf()
 
-    private var visibleChanged: (Boolean) -> Unit = {}
+    private val visibleChangedListeners: MutableList<(Boolean) -> Unit> = mutableListOf()
 
     private var appVisible = false
         private set(value) {
             if (field != value) {
                 field = value
 
-                visibleChanged(value)
+                visibleChangedListeners.forEach { listener ->
+                    listener(value)
+                }
             }
         }
 
@@ -55,7 +57,7 @@ object ApplicationObserver {
     }
 
     fun onVisibleChanged(visibleChanged: (Boolean) -> Unit) {
-        this.visibleChanged = visibleChanged
+        visibleChangedListeners.add(visibleChanged)
     }
 
     fun attach(application: Application) {
diff --git a/design/src/main/java/com/github/kr328/clash/design/AppSettingsDesign.kt b/design/src/main/java/com/github/kr328/clash/design/AppSettingsDesign.kt
index dc43d00a29..de1ef20c92 100644
--- a/design/src/main/java/com/github/kr328/clash/design/AppSettingsDesign.kt
+++ b/design/src/main/java/com/github/kr328/clash/design/AppSettingsDesign.kt
@@ -88,6 +88,13 @@ class AppSettingsDesign(
                 }
             }
 
+            switch(
+                value = uiStore::autoDestroyUI,
+                icon = R.drawable.ic_baseline_close,
+                title = R.string.auto_destroy_ui_title,
+                summary = R.string.auto_destroy_ui_desc,
+            )
+
             category(R.string.service)
 
             switch(
diff --git a/design/src/main/java/com/github/kr328/clash/design/store/UiStore.kt b/design/src/main/java/com/github/kr328/clash/design/store/UiStore.kt
index ddc9d600fd..3eca036234 100644
--- a/design/src/main/java/com/github/kr328/clash/design/store/UiStore.kt
+++ b/design/src/main/java/com/github/kr328/clash/design/store/UiStore.kt
@@ -41,6 +41,11 @@ class UiStore(context: Context) {
         defaultValue = false,
     )
 
+    var autoDestroyUI: Boolean by store.boolean(
+        key = "auto_destroy_ui",
+        defaultValue = false,
+    )
+
     var proxyExcludeNotSelectable by store.boolean(
         key = "proxy_exclude_not_selectable",
         defaultValue = false,
diff --git a/design/src/main/res/values-ja-rJP/strings.xml b/design/src/main/res/values-ja-rJP/strings.xml
index e38b8bf030..028991524c 100644
--- a/design/src/main/res/values-ja-rJP/strings.xml
+++ b/design/src/main/res/values-ja-rJP/strings.xml
@@ -264,4 +264,6 @@
     <string name="override_destination">Override Destination</string>
     <string name="import_from_qr_no_permission">カメラのアクセスが制限されています。設定から有効にしてください。</string>
     <string name="import_from_qr_exception">システムで予期しない例外が発生しました。</string>
+    <string name="auto_destroy_ui_title">UI自動破棄</string>
+    <string name="auto_destroy_ui_desc">アプリがバックグラウンドに移行して3秒後にメモリ節約のためUIを自動的に破棄します</string>
 </resources>
diff --git a/design/src/main/res/values-ko-rKR/strings.xml b/design/src/main/res/values-ko-rKR/strings.xml
index bc22550af8..82e9bf686c 100644
--- a/design/src/main/res/values-ko-rKR/strings.xml
+++ b/design/src/main/res/values-ko-rKR/strings.xml
@@ -264,4 +264,6 @@
     <string name="override_destination">Override Destination</string>
     <string name="import_from_qr_no_permission">카메라 접근이 제한되었습니다. 설정에서 허용해 주세요.</string>
     <string name="import_from_qr_exception">처리되지 않은 시스템 예외가 발생했습니다.</string>
+    <string name="auto_destroy_ui_title">UI 자동 종료</string>
+    <string name="auto_destroy_ui_desc">앱이 백그라운드로 전환된 후 3초 후 메모리 절약을 위해 UI를 자동으로 종료합니다</string>
 </resources>
diff --git a/design/src/main/res/values-ru/strings.xml b/design/src/main/res/values-ru/strings.xml
index 4f680de2c5..83dcc9dc0f 100644
--- a/design/src/main/res/values-ru/strings.xml
+++ b/design/src/main/res/values-ru/strings.xml
@@ -328,4 +328,6 @@
     <string name="override_destination">Override Destination</string>
     <string name="import_from_qr_no_permission">Доступ к камере ограничен. Разрешите его в настройках.</string>
     <string name="import_from_qr_exception">Произошла не обрабатываемая системная ошибка.</string>
+    <string name="auto_destroy_ui_title">Автоуничтожение UI</string>
+    <string name="auto_destroy_ui_desc">Автоматически уничтожать UI через 3 секунды после перехода приложения в фон для экономии памяти</string>
 </resources>
diff --git a/design/src/main/res/values-vi/strings.xml b/design/src/main/res/values-vi/strings.xml
index 2abca48934..befb8f1691 100644
--- a/design/src/main/res/values-vi/strings.xml
+++ b/design/src/main/res/values-vi/strings.xml
@@ -250,4 +250,6 @@
     <string name="import_from_qr">Nhập từ Mã QR</string>
     <string name="import_from_qr_no_permission">Quyền truy cập camera bị hạn chế. Vui lòng bật trong Cài đặt.</string>
     <string name="import_from_qr_exception">Đã xảy ra ngoại lệ hệ thống không xử lý được.</string>
+    <string name="auto_destroy_ui_title">Tự động hủy UI</string>
+    <string name="auto_destroy_ui_desc">Tự động hủy UI sau 3 giây khi ứng dụng chuyển sang nền để tiết kiệm bộ nhớ</string>
 </resources>
diff --git a/design/src/main/res/values-zh-rHK/strings.xml b/design/src/main/res/values-zh-rHK/strings.xml
index a63dff70a4..d87a1bb18e 100644
--- a/design/src/main/res/values-zh-rHK/strings.xml
+++ b/design/src/main/res/values-zh-rHK/strings.xml
@@ -261,4 +261,6 @@
     <string name="override_destination">Override Destination</string>
     <string name="import_from_qr_no_permission">相機權限受限，請前往設定開啟。</string>
     <string name="import_from_qr_exception">發生系統未知異常，操作失敗。</string>
+    <string name="auto_destroy_ui_title">自動銷毀介面</string>
+    <string name="auto_destroy_ui_desc">應用程式進入背景3秒後自動銷毀介面以節省記憶體</string>
 </resources>
diff --git a/design/src/main/res/values-zh-rTW/strings.xml b/design/src/main/res/values-zh-rTW/strings.xml
index 4bc185b77d..14cf639b6a 100644
--- a/design/src/main/res/values-zh-rTW/strings.xml
+++ b/design/src/main/res/values-zh-rTW/strings.xml
@@ -261,4 +261,6 @@
     <string name="override_destination">Override Destination</string>
     <string name="import_from_qr_no_permission">相機權限受限，請前往設定開啟。</string>
     <string name="import_from_qr_exception">發生系統未知異常，操作失敗。</string>
+    <string name="auto_destroy_ui_title">自動銷毀介面</string>
+    <string name="auto_destroy_ui_desc">應用程式進入背景3秒後自動銷毀介面以節省記憶體</string>
 </resources>
diff --git a/design/src/main/res/values-zh/strings.xml b/design/src/main/res/values-zh/strings.xml
index be62f50f54..f94f33d7fa 100644
--- a/design/src/main/res/values-zh/strings.xml
+++ b/design/src/main/res/values-zh/strings.xml
@@ -41,6 +41,8 @@
     <string name="hide_app_icon_desc">可以在拨号盘输入 *#*#252746382#*#* 打开应用</string>
     <string name="hide_from_recents_title">从最近任务隐藏</string>
     <string name="hide_from_recents_desc">在最近任务中隐藏应用</string>
+    <string name="auto_destroy_ui_title">自动销毁界面</string>
+    <string name="auto_destroy_ui_desc">应用进入后台3秒后自动销毁界面以节省内存</string>
     <string name="history">历史</string>
     <string name="import_from_file">从文件导入</string>
     <string name="import_from_url">从 URL 导入</string>
diff --git a/design/src/main/res/values/strings.xml b/design/src/main/res/values/strings.xml
index 2fe54fd226..8a6ee26474 100644
--- a/design/src/main/res/values/strings.xml
+++ b/design/src/main/res/values/strings.xml
@@ -361,6 +361,8 @@
     <string name="hide_app_icon_desc">You can dial *#*#252746382#*#* to open this App</string>
     <string name="hide_from_recents_title">Hide from Recents</string>
     <string name="hide_from_recents_desc">Hide app from the Recent apps screen</string>
+    <string name="auto_destroy_ui_title">Auto Destroy UI</string>
+    <string name="auto_destroy_ui_desc">Automatically destroy UI after 3 seconds when app goes to background</string>
     <string name="import_from_qr_no_permission">Camera access is restricted. Please enable it in Settings.</string>
     <string name="import_from_qr_exception">An unhandled system exception occurred.</string>