diff --git a/sdk/src/commonMain/kotlin/com/base44/sdk/Base44Client.kt b/sdk/src/commonMain/kotlin/com/base44/sdk/Base44Client.kt
index 53e9f71..cf908d8 100644
--- a/sdk/src/commonMain/kotlin/com/base44/sdk/Base44Client.kt
+++ b/sdk/src/commonMain/kotlin/com/base44/sdk/Base44Client.kt
@@ -131,7 +131,7 @@ class ServiceRoleClient internal constructor(
  */
 fun createClient(config: CreateClientConfig): Base44Client {
     val baseUrl = "${config.serverUrl}/api"
-    val baseHeaders = config.headers + mapOf("X-App-Id" to config.appId)
+    val baseHeaders = config.headers
     val functionHeaders = if (config.functionsVersion != null)
         baseHeaders + mapOf("Base44-Functions-Version" to config.functionsVersion)
     else baseHeaders
diff --git a/sdk/src/commonTest/kotlin/com/base44/sdk/EntitiesModuleTest.kt b/sdk/src/commonTest/kotlin/com/base44/sdk/EntitiesModuleTest.kt
index 594aa02..4b73d04 100644
--- a/sdk/src/commonTest/kotlin/com/base44/sdk/EntitiesModuleTest.kt
+++ b/sdk/src/commonTest/kotlin/com/base44/sdk/EntitiesModuleTest.kt
@@ -226,10 +226,10 @@ class HttpClientTest {
     }
 
     @Test
-    fun testXAppIdHeaderSent() = runTest {
+    fun testCustomHeadersForwarded() = runTest {
         val mockEngine = MockEngine { request ->
-            val appId = request.headers["X-App-Id"]
-            assertEquals("my-app-123", appId)
+            val customHeader = request.headers["X-Custom-Header"]
+            assertEquals("my-value-123", customHeader)
             respond(
                 content = ByteReadChannel("{}"),
                 status = HttpStatusCode.OK,
@@ -238,7 +238,7 @@ class HttpClientTest {
         }
         val client = Base44HttpClient(
             baseUrl = "https://base44.app/api",
-            initialHeaders = mapOf("X-App-Id" to "my-app-123"),
+            initialHeaders = mapOf("X-Custom-Header" to "my-value-123"),
             httpClient = HttpClient(mockEngine),
         )
         client.get("/test")