diff --git a/packages/react-native/Libraries/Core/setUpReactDevTools.js b/packages/react-native/Libraries/Core/setUpReactDevTools.js
index 9bdf66b30184..92efa8df39fe 100644
--- a/packages/react-native/Libraries/Core/setUpReactDevTools.js
+++ b/packages/react-native/Libraries/Core/setUpReactDevTools.js
@@ -146,17 +146,36 @@ if (__DEV__) {
         ? guessHostFromDevServerUrl(devServer.url)
         : 'localhost';
 
-      // Read the optional global variable for backward compatibility.
-      // It was added in https://github.com/facebook/react-native/commit/bf2b435322e89d0aeee8792b1c6e04656c2719a0.
-      const port =
+      // Derive scheme and port from the dev server URL when possible,
+      // falling back to ws://host:8097 for local development.
+      let wsScheme = 'ws';
+      let port = 8097;
+
+      if (
         // $FlowFixMe[prop-missing]
         // $FlowFixMe[incompatible-use]
         window.__REACT_DEVTOOLS_PORT__ != null
-          ? window.__REACT_DEVTOOLS_PORT__
-          : 8097;
+      ) {
+        // $FlowFixMe[prop-missing]
+        port = window.__REACT_DEVTOOLS_PORT__;
+      } else if (devServer.bundleLoadedFromServer) {
+        try {
+          const devUrl = new URL(devServer.url);
+          if (devUrl.protocol === 'https:') {
+            wsScheme = 'wss';
+          }
+          if (devUrl.port) {
+            port = parseInt(devUrl.port, 10);
+          } else if (devUrl.protocol === 'https:') {
+            port = 443;
+          } else {
+            port = 80;
+          }
+        } catch (e) {}
+      }
 
       const WebSocket = require('../WebSocket/WebSocket').default;
-      ws = new WebSocket('ws://' + host + ':' + port);
+      ws = new WebSocket(wsScheme + '://' + host + ':' + port);
       ws.addEventListener('close', event => {
         isWebSocketOpen = false;
       });
diff --git a/packages/react-native/Libraries/Network/RCTHTTPRequestHandler.mm b/packages/react-native/Libraries/Network/RCTHTTPRequestHandler.mm
index 0303970a2e47..e7017453b147 100644
--- a/packages/react-native/Libraries/Network/RCTHTTPRequestHandler.mm
+++ b/packages/react-native/Libraries/Network/RCTHTTPRequestHandler.mm
@@ -9,6 +9,7 @@
 
 #import <mutex>
 
+#import <React/RCTDevSupportHttpHeaders.h>
 #import <React/RCTNetworking.h>
 #import <ReactCommon/RCTTurboModule.h>
 
@@ -99,7 +100,9 @@ - (NSURLSessionDataTask *)sendRequest:(NSURLRequest *)request withDelegate:(id<R
                                            valueOptions:NSPointerFunctionsStrongMemory
                                                capacity:0];
   }
-  NSURLSessionDataTask *task = [_session dataTaskWithRequest:request];
+  NSMutableURLRequest *mutableRequest = [request mutableCopy];
+  [[RCTDevSupportHttpHeaders sharedInstance] applyHeadersToRequest:mutableRequest];
+  NSURLSessionDataTask *task = [_session dataTaskWithRequest:mutableRequest];
   [_delegates setObject:delegate forKey:task];
   [task resume];
   return task;
diff --git a/packages/react-native/React/Base/RCTDevSupportHttpHeaders.h b/packages/react-native/React/Base/RCTDevSupportHttpHeaders.h
index e73cdd3c4b88..7e19dbe43111 100644
--- a/packages/react-native/React/Base/RCTDevSupportHttpHeaders.h
+++ b/packages/react-native/React/Base/RCTDevSupportHttpHeaders.h
@@ -17,7 +17,9 @@
 + (instancetype)sharedInstance;
 
 - (void)addRequestHeader:(NSString *)name value:(NSString *)value;
+- (void)addRequestHeader:(NSString *)name value:(NSString *)value forHost:(NSString *)host;
 - (void)removeRequestHeader:(NSString *)name;
+- (void)removeRequestHeader:(NSString *)name forHost:(NSString *)host;
 - (NSDictionary<NSString *, NSString *> *)allHeaders;
 - (void)applyHeadersToRequest:(NSMutableURLRequest *)request;
 
diff --git a/packages/react-native/React/Base/RCTDevSupportHttpHeaders.m b/packages/react-native/React/Base/RCTDevSupportHttpHeaders.m
index 0717537f8424..0b6d5c8275a7 100644
--- a/packages/react-native/React/Base/RCTDevSupportHttpHeaders.m
+++ b/packages/react-native/React/Base/RCTDevSupportHttpHeaders.m
@@ -9,6 +9,7 @@
 
 @implementation RCTDevSupportHttpHeaders {
   NSMutableDictionary<NSString *, NSString *> *_headers;
+  NSMutableDictionary<NSString *, NSMutableDictionary<NSString *, NSString *> *> *_hostHeaders;
   dispatch_queue_t _queue;
 }
 
@@ -26,6 +27,7 @@ - (instancetype)init
 {
   if (self = [super init]) {
     _headers = [NSMutableDictionary new];
+    _hostHeaders = [NSMutableDictionary new];
     _queue = dispatch_queue_create("com.facebook.react.RCTDevSupportHttpHeaders", DISPATCH_QUEUE_SERIAL);
   }
   return self;
@@ -38,6 +40,18 @@ - (void)addRequestHeader:(NSString *)name value:(NSString *)value
   });
 }
 
+- (void)addRequestHeader:(NSString *)name value:(NSString *)value forHost:(NSString *)host
+{
+  dispatch_sync(_queue, ^{
+    NSMutableDictionary<NSString *, NSString *> *headersForHost = self->_hostHeaders[host];
+    if (headersForHost == nil) {
+      headersForHost = [NSMutableDictionary new];
+      self->_hostHeaders[host] = headersForHost;
+    }
+    headersForHost[name] = value;
+  });
+}
+
 - (void)removeRequestHeader:(NSString *)name
 {
   dispatch_sync(_queue, ^{
@@ -45,6 +59,19 @@ - (void)removeRequestHeader:(NSString *)name
   });
 }
 
+- (void)removeRequestHeader:(NSString *)name forHost:(NSString *)host
+{
+  dispatch_sync(_queue, ^{
+    NSMutableDictionary<NSString *, NSString *> *headersForHost = self->_hostHeaders[host];
+    if (headersForHost != nil) {
+      [headersForHost removeObjectForKey:name];
+      if (headersForHost.count == 0) {
+        [self->_hostHeaders removeObjectForKey:host];
+      }
+    }
+  });
+}
+
 - (NSDictionary<NSString *, NSString *> *)allHeaders
 {
   __block NSDictionary<NSString *, NSString *> *snapshot;
@@ -56,8 +83,23 @@ - (void)removeRequestHeader:(NSString *)name
 
 - (void)applyHeadersToRequest:(NSMutableURLRequest *)request
 {
-  NSDictionary<NSString *, NSString *> *headers = [self allHeaders];
-  [headers enumerateKeysAndObjectsUsingBlock:^(NSString *headerName, NSString *headerValue, BOOL *stop) {
+  __block NSDictionary<NSString *, NSString *> *globalHeaders;
+  __block NSDictionary<NSString *, NSString *> *hostSpecificHeaders;
+
+  NSString *requestHost = request.URL.host;
+
+  dispatch_sync(_queue, ^{
+    globalHeaders = [self->_headers copy];
+    if (requestHost != nil && self->_hostHeaders[requestHost] != nil) {
+      hostSpecificHeaders = [self->_hostHeaders[requestHost] copy];
+    }
+  });
+
+  [globalHeaders enumerateKeysAndObjectsUsingBlock:^(NSString *headerName, NSString *headerValue, BOOL *stop) {
+    [request setValue:headerValue forHTTPHeaderField:headerName];
+  }];
+
+  [hostSpecificHeaders enumerateKeysAndObjectsUsingBlock:^(NSString *headerName, NSString *headerValue, BOOL *stop) {
     [request setValue:headerValue forHTTPHeaderField:headerName];
   }];
 }
diff --git a/packages/react-native/React/CoreModules/RCTWebSocketModule.mm b/packages/react-native/React/CoreModules/RCTWebSocketModule.mm
index 27f53f88dd85..a3ca77ede88d 100644
--- a/packages/react-native/React/CoreModules/RCTWebSocketModule.mm
+++ b/packages/react-native/React/CoreModules/RCTWebSocketModule.mm
@@ -12,6 +12,7 @@
 #import <FBReactNativeSpec/FBReactNativeSpec.h>
 #import <React/RCTAssert.h>
 #import <React/RCTConvert.h>
+#import <React/RCTDevSupportHttpHeaders.h>
 #import <React/RCTUtils.h>
 #import <SocketRocket/SRWebSocket.h>
 
@@ -114,6 +115,8 @@ - (void)invalidate
     }];
   }
 
+  [[RCTDevSupportHttpHeaders sharedInstance] applyHeadersToRequest:request];
+
   SRWebSocket *webSocket = [[SRWebSocket alloc] initWithURLRequest:request protocols:protocols];
   [webSocket setDelegateDispatchQueue:[self methodQueue]];
   webSocket.delegate = self;
diff --git a/packages/react-native/React/DevSupport/RCTInspectorDevServerHelper.mm b/packages/react-native/React/DevSupport/RCTInspectorDevServerHelper.mm
index 36e18415eed3..fdc5628137a0 100644
--- a/packages/react-native/React/DevSupport/RCTInspectorDevServerHelper.mm
+++ b/packages/react-native/React/DevSupport/RCTInspectorDevServerHelper.mm
@@ -23,25 +23,29 @@
 
 static NSString *getServerHost(NSURL *bundleURL)
 {
-  NSNumber *port = @8081;
-  NSString *portStr = [[[NSProcessInfo processInfo] environment] objectForKey:@"RCT_METRO_PORT"];
-  if ((portStr != nullptr) && [portStr length] > 0) {
-    port = [NSNumber numberWithInt:[portStr intValue]];
-  }
-  if ([bundleURL port] != nullptr) {
-    port = [bundleURL port];
-  }
   NSString *host = [bundleURL host];
   if (host == nullptr) {
     host = @"localhost";
   }
 
-  // this is consistent with the Android implementation, where http:// is the
-  // hardcoded implicit scheme for the debug server. Note, packagerURL
-  // technically looks like it could handle schemes/protocols other than HTTP,
-  // so rather than force HTTP, leave it be for now, in case someone is relying
-  // on that ability when developing against iOS.
-  return [NSString stringWithFormat:@"%@:%@", host, port];
+  // Use explicit port from URL if available
+  if ([bundleURL port] != nullptr) {
+    return [NSString stringWithFormat:@"%@:%@", host, [bundleURL port]];
+  }
+
+  // Check environment variable
+  NSString *portStr = [[[NSProcessInfo processInfo] environment] objectForKey:@"RCT_METRO_PORT"];
+  if ((portStr != nullptr) && [portStr length] > 0) {
+    return [NSString stringWithFormat:@"%@:%@", host, portStr];
+  }
+
+  // For https, omit port — the scheme implies 443
+  if ([[bundleURL scheme] isEqualToString:@"https"]) {
+    return host;
+  }
+
+  // Default to 8081 for local development (Metro's default port)
+  return [NSString stringWithFormat:@"%@:%@", host, @8081];
 }
 
 static NSString *getSHA256(NSString *string)
@@ -112,13 +116,15 @@
   NSString *escapedInspectorDeviceId = [getInspectorDeviceId()
       stringByAddingPercentEncodingWithAllowedCharacters:NSCharacterSet.URLQueryAllowedCharacterSet];
 
-  return [NSURL
-      URLWithString:[NSString stringWithFormat:@"http://%@/inspector/device?name=%@&app=%@&device=%@&profiling=%@",
-                                               getServerHost(bundleURL),
-                                               escapedDeviceName,
-                                               escapedAppName,
-                                               escapedInspectorDeviceId,
-                                               isProfilingBuild ? @"true" : @"false"]];
+  NSString *scheme = [bundleURL scheme] ?: @"http";
+  return
+      [NSURL URLWithString:[NSString stringWithFormat:@"%@://%@/inspector/device?name=%@&app=%@&device=%@&profiling=%@",
+                                                      scheme,
+                                                      getServerHost(bundleURL),
+                                                      escapedDeviceName,
+                                                      escapedAppName,
+                                                      escapedInspectorDeviceId,
+                                                      isProfilingBuild ? @"true" : @"false"]];
 }
 
 @implementation RCTInspectorDevServerHelper
@@ -150,7 +156,9 @@ + (void)openDebugger:(NSURL *)bundleURL withErrorMessage:(NSString *)errorMessag
   NSString *escapedInspectorDeviceId = [getInspectorDeviceId()
       stringByAddingPercentEncodingWithAllowedCharacters:NSCharacterSet.URLQueryAllowedCharacterSet];
 
-  NSURL *url = [NSURL URLWithString:[NSString stringWithFormat:@"http://%@/open-debugger?device=%@",
+  NSString *scheme = [bundleURL scheme] ?: @"http";
+  NSURL *url = [NSURL URLWithString:[NSString stringWithFormat:@"%@://%@/open-debugger?device=%@",
+                                                               scheme,
                                                                getServerHost(bundleURL),
                                                                escapedInspectorDeviceId]];
   NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url];
diff --git a/packages/react-native/ReactAndroid/src/main/java/com/facebook/react/devsupport/inspector/DevSupportHttpClient.kt b/packages/react-native/ReactAndroid/src/main/java/com/facebook/react/devsupport/inspector/DevSupportHttpClient.kt
index dae61b4309bd..01cb7eece216 100644
--- a/packages/react-native/ReactAndroid/src/main/java/com/facebook/react/devsupport/inspector/DevSupportHttpClient.kt
+++ b/packages/react-native/ReactAndroid/src/main/java/com/facebook/react/devsupport/inspector/DevSupportHttpClient.kt
@@ -21,12 +21,20 @@ import okhttp3.OkHttpClient
  */
 public object DevSupportHttpClient {
   private val customHeaders = ConcurrentHashMap<String, String>()
+  private val hostHeaders = ConcurrentHashMap<String, ConcurrentHashMap<String, String>>()
 
   private val headerInterceptor = Interceptor { chain ->
-    val builder = chain.request().newBuilder()
+    val request = chain.request()
+    val builder = request.newBuilder()
     for ((name, value) in customHeaders) {
       builder.header(name, value)
     }
+    val host = request.url().host()
+    hostHeaders[host]?.let { headersForHost ->
+      for ((name, value) in headersForHost) {
+        builder.header(name, value)
+      }
+    }
     chain.proceed(builder.build())
   }
 
@@ -53,12 +61,29 @@ public object DevSupportHttpClient {
     customHeaders[name] = value
   }
 
+  /** Add a custom header that is only applied to requests matching the given host. */
+  @JvmStatic
+  public fun addRequestHeader(name: String, value: String, host: String) {
+    hostHeaders.getOrPut(host) { ConcurrentHashMap() }[name] = value
+  }
+
   /** Remove a previously added custom header. */
   @JvmStatic
   public fun removeRequestHeader(name: String) {
     customHeaders.remove(name)
   }
 
+  /** Remove a previously added host-specific custom header. */
+  @JvmStatic
+  public fun removeRequestHeader(name: String, host: String) {
+    hostHeaders[host]?.let { headersForHost ->
+      headersForHost.remove(name)
+      if (headersForHost.isEmpty()) {
+        hostHeaders.remove(host)
+      }
+    }
+  }
+
   /**
    * Returns the appropriate HTTP scheme ("http" or "https") for the given host. Uses "https" when
    * the host specifies port 443 explicitly (e.g. "example.com:443").
diff --git a/packages/react-native/ReactAndroid/src/main/java/com/facebook/react/modules/network/OkHttpClientProvider.kt b/packages/react-native/ReactAndroid/src/main/java/com/facebook/react/modules/network/OkHttpClientProvider.kt
index b753b07b892e..ebccd2bb7580 100644
--- a/packages/react-native/ReactAndroid/src/main/java/com/facebook/react/modules/network/OkHttpClientProvider.kt
+++ b/packages/react-native/ReactAndroid/src/main/java/com/facebook/react/modules/network/OkHttpClientProvider.kt
@@ -8,6 +8,7 @@
 package com.facebook.react.modules.network
 
 import android.content.Context
+import com.facebook.react.devsupport.inspector.DevSupportHttpClient
 import java.io.File
 import java.util.concurrent.TimeUnit
 import okhttp3.Cache
@@ -47,8 +48,10 @@ public object OkHttpClientProvider {
   @JvmStatic
   public fun createClientBuilder(): OkHttpClient.Builder {
     // No timeouts by default
+    // Use DevSupportHttpClient as base to inherit custom header interceptor
     val client: OkHttpClient.Builder =
-        OkHttpClient.Builder()
+        DevSupportHttpClient.httpClient
+            .newBuilder()
             .connectTimeout(0, TimeUnit.MILLISECONDS)
             .readTimeout(0, TimeUnit.MILLISECONDS)
             .writeTimeout(0, TimeUnit.MILLISECONDS)
diff --git a/packages/react-native/ReactAndroid/src/main/java/com/facebook/react/modules/websocket/WebSocketModule.kt b/packages/react-native/ReactAndroid/src/main/java/com/facebook/react/modules/websocket/WebSocketModule.kt
index 9c8d9cf1240e..76e73c4e3b13 100644
--- a/packages/react-native/ReactAndroid/src/main/java/com/facebook/react/modules/websocket/WebSocketModule.kt
+++ b/packages/react-native/ReactAndroid/src/main/java/com/facebook/react/modules/websocket/WebSocketModule.kt
@@ -19,6 +19,7 @@ import com.facebook.react.bridge.ReadableType
 import com.facebook.react.bridge.WritableMap
 import com.facebook.react.bridge.buildReadableMap
 import com.facebook.react.common.ReactConstants
+import com.facebook.react.devsupport.inspector.DevSupportHttpClient
 import com.facebook.react.module.annotations.ReactModule
 import com.facebook.react.modules.network.CustomClientBuilder
 import com.facebook.react.modules.network.ForwardingCookieHandler
@@ -80,7 +81,8 @@ public class WebSocketModule(context: ReactApplicationContext) :
   ) {
     val id = socketID.toInt()
     val okHttpBuilder =
-        OkHttpClient.Builder()
+        DevSupportHttpClient.httpClient
+            .newBuilder()
             .connectTimeout(10, TimeUnit.SECONDS)
             .writeTimeout(10, TimeUnit.SECONDS)
             .readTimeout(0, TimeUnit.MINUTES) // Disable timeouts for read
@@ -199,8 +201,9 @@ public class WebSocketModule(context: ReactApplicationContext) :
         },
     )
 
-    // Trigger shutdown of the dispatcher's executor so this process can exit cleanly
-    client.dispatcher().executorService().shutdown()
+    // Note: Do NOT call client.dispatcher().executorService().shutdown() here.
+    // When building from a shared OkHttpClient (DevSupportHttpClient), the dispatcher
+    // is shared across all clients. Shutting it down would kill all connections.
   }
 
   override fun close(code: Double, reason: String?, socketID: Double) {