mDNS tweaks

platformio.ini

@@ -30,6 +30,9 @@ build_flags =
   -std=c++2a
 # Enable UTF-8 long file names in SdFat
   -DUSE_UTF8_LONG_NAMES=1
+# mDNS service discovery for companion app network scanning
+  -DMDNS_SERVICE_DISCOVERY=1
+  -DMDNS_SERVICE_TXT_RECORDS=1
 
 ; Board configuration
 board_build.flash_mode = dio

src/activities/network/CrossPointWebServerActivity.cpp

@@ -25,6 +25,32 @@ constexpr uint8_t AP_MAX_CONNECTIONS = 4;
 // DNS server for captive portal (redirects all DNS queries to our IP)
 DNSServer* dnsServer = nullptr;
 constexpr uint16_t DNS_PORT = 53;
+
+// mDNS service discovery - advertises the device for network scanning
+// Controlled by build flags in platformio.ini:
+//   MDNS_SERVICE_DISCOVERY   - enables service advertisement (required for Android NSD)
+//   MDNS_SERVICE_TXT_RECORDS - enables TXT record metadata (device type, ports)
+void setupMdnsServiceDiscovery(uint16_t httpPort, uint16_t wsPort) {
+#if MDNS_SERVICE_DISCOVERY
+  // Advertise HTTP service for network discovery (required for Android NSD)
+  MDNS.addService("http", "tcp", httpPort);
+  Serial.printf("[%lu] [WEBACT] mDNS service advertised: _http._tcp port %d\n", millis(), httpPort);
+
+#if MDNS_SERVICE_TXT_RECORDS
+  // Add TXT records with device info for enhanced discovery
+  MDNS.addServiceTxt("http", "tcp", "device", "crosspoint");
+  MDNS.addServiceTxt("http", "tcp", "wsPort", String(wsPort).c_str());
+  Serial.printf("[%lu] [WEBACT] mDNS TXT records added (device=crosspoint, wsPort=%d)\n", millis(), wsPort);
+#else
+  (void)wsPort;
+#endif
+
+#else
+  (void)httpPort;
+  (void)wsPort;
+  Serial.printf("[%lu] [WEBACT] mDNS service discovery disabled\n", millis());
+#endif
+}
 }  // namespace
 
 void CrossPointWebServerActivity::taskTrampoline(void* param) {
@@ -167,6 +193,7 @@ void CrossPointWebServerActivity::onWifiSelectionComplete(const bool connected)
     // Start mDNS for hostname resolution
     if (MDNS.begin(AP_HOSTNAME)) {
       Serial.printf("[%lu] [WEBACT] mDNS started: http://%s.local/\n", millis(), AP_HOSTNAME);
+      setupMdnsServiceDiscovery(80, 81);
     }
 
     // Start the web server
@@ -220,6 +247,7 @@ void CrossPointWebServerActivity::startAccessPoint() {
   // Start mDNS for hostname resolution
   if (MDNS.begin(AP_HOSTNAME)) {
     Serial.printf("[%lu] [WEBACT] mDNS started: http://%s.local/\n", millis(), AP_HOSTNAME);
+    setupMdnsServiceDiscovery(80, 81);
   } else {
     Serial.printf("[%lu] [WEBACT] WARNING: mDNS failed to start\n", millis());
   }