diff --git a/components/modules/web/app_mdns.c b/components/modules/web/app_mdns.c
index bb3558f..b6d1785 100644
--- a/components/modules/web/app_mdns.c
+++ b/components/modules/web/app_mdns.c
@@ -180,6 +180,7 @@ void app_mdns_main()
 	}
 	xSemaphoreGive(query_lock);
 
+    // must be called after camera initialization
     sensor_t * s = esp_camera_sensor_get();
     if(s == NULL){
         ESP_LOGE(TAG, "esp_camera_sensor_get() Failed");
diff --git a/examples/cat_face_detection/web/main/app_main.cpp b/examples/cat_face_detection/web/main/app_main.cpp
index 41c3a28..281b4b0 100755
--- a/examples/cat_face_detection/web/main/app_main.cpp
+++ b/examples/cat_face_detection/web/main/app_main.cpp
@@ -10,12 +10,12 @@ static QueueHandle_t xQueueHttpFrame = NULL;
 extern "C" void app_main()
 {
     app_wifi_main();
-    app_mdns_main();
 
     xQueueAIFrame = xQueueCreate(2, sizeof(camera_fb_t *));
     xQueueHttpFrame = xQueueCreate(2, sizeof(camera_fb_t *));
 
     register_camera(PIXFORMAT_RGB565, FRAMESIZE_QVGA, 2, xQueueAIFrame);
+    app_mdns_main();
     register_cat_face_detection(xQueueAIFrame, NULL, NULL, xQueueHttpFrame);
     register_httpd(xQueueHttpFrame, NULL, true);
-}
+}
\ No newline at end of file
diff --git a/examples/human_face_detection/web/main/app_main.cpp b/examples/human_face_detection/web/main/app_main.cpp
index e208a83..97c7795 100755
--- a/examples/human_face_detection/web/main/app_main.cpp
+++ b/examples/human_face_detection/web/main/app_main.cpp
@@ -10,12 +10,12 @@ static QueueHandle_t xQueueHttpFrame = NULL;
 extern "C" void app_main()
 {
     app_wifi_main();
-    app_mdns_main();
 
     xQueueAIFrame = xQueueCreate(2, sizeof(camera_fb_t *));
     xQueueHttpFrame = xQueueCreate(2, sizeof(camera_fb_t *));
 
     register_camera(PIXFORMAT_RGB565, FRAMESIZE_QVGA, 2, xQueueAIFrame);
+    app_mdns_main();
     register_human_face_detection(xQueueAIFrame, NULL, NULL, xQueueHttpFrame);
     register_httpd(xQueueHttpFrame, NULL, true);
 }
diff --git a/examples/motion_detection/web/main/app_main.cpp b/examples/motion_detection/web/main/app_main.cpp
index 42769ca..45135de 100755
--- a/examples/motion_detection/web/main/app_main.cpp
+++ b/examples/motion_detection/web/main/app_main.cpp
@@ -10,12 +10,12 @@ static QueueHandle_t xQueueHttpFrame = NULL;
 extern "C" void app_main()
 {
     app_wifi_main();
-    app_mdns_main();
 
     xQueueAIFrame = xQueueCreate(2, sizeof(camera_fb_t *));
     xQueueHttpFrame = xQueueCreate(2, sizeof(camera_fb_t *));
 
     register_camera(PIXFORMAT_RGB565, FRAMESIZE_QVGA, 2, xQueueAIFrame);
+    app_mdns_main();
     register_motion_detection(xQueueAIFrame, NULL, NULL, xQueueHttpFrame);
     register_httpd(xQueueHttpFrame, NULL, true);
 }