Added LED note about startup LEDs and activity LEDs

applications/README.md

@@ -1,4 +1,35 @@
 # Applications
+
+This page describes the various application this repository has available and how they generally operate.
+
+<br />
+
+## LED indicator
+---
+The XPLR-IoT-1 development platform has a RGB LED indicator on the front of the box. This application framework allows the application to set the LEDs independently, with various flashing and blinking modes. 
+
+### Application startup LED indicator
+The Boot, Registration, MQTT activity and cell scanning activity has the following LED statuses:
+
+- Turn on: Solid RED 
+- Option choice (Display/Delete log file): Solid Blue
+- XPLR initialization: Flashing red
+- Network Registration: Flashing Blue
+- Connecting to MQTT: Flashing Green
+- Operating: Green
+- Shutdown: Solid Red (Button #1)
+- Off: No LED (Safely turn off)
+
+### Activity LED indicator
+
+- Published MQTT message: Blip Green
+- Cell Scan: Blue / Blip Blue
+
+
+<br />
+
+# Application List
+
 (Currently this repository has only one application).
 
 * [Cellular Tracker](cellular_tracker/).