diff --git a/README.rst b/README.rst
index 6d80324..347d152 100644
--- a/README.rst
+++ b/README.rst
@@ -257,3 +257,7 @@ application (and the "blank" white screen is a torch application):
 .. image:: res/WordClkApp.png
    :alt: Shows a time as words in the wasp-os simulator
    :width: 179
+
+.. image:: res/BeaconApp.png
+   :alt: Flash the relatively powerful HRS LED repeatedly
+   :width: 179
diff --git a/apps/Beacon.py b/apps/Beacon.py
new file mode 100644
index 0000000..7676fff
--- /dev/null
+++ b/apps/Beacon.py
@@ -0,0 +1,130 @@
+# SPDX-License-Identifier: LGPL-3.0-or-later
+# Copyright (C) 2021 Francesco Gazzetta
+"""Beacon application
+~~~~~~~~~~~~~~~~~~~~~
+
+Flash the relatively powerful HRS LED repeatedly, mostly for signaling purposes.
+
+Frequency and intensity can be changed.
+
+The blinking is handled by the HRS, so this app consumes very little power.
+With BLE and/or step counter disabled and blinking frequency set to the minimum,
+the watch's battery will last for many days.
+
+.. figure:: res/BeaconApp.png
+    :width: 179
+"""
+
+import wasp
+import machine
+from micropython import const
+
+_ENABLE = const(0x01)
+_PDRIVER = const(0x0c)
+
+_ENABLE_HEN = const(0x80)
+_ENABLE_PDRIVE1 = const(0x08)
+_PDRIVER_PDRIVE0 = const(0x40)
+_ENABLE_HWT = const(0x70)
+
+class BeaconApp():
+    NAME = "Beacon"
+    # 2-bit RLE, 96x64, generated from res/beacon_icon.png, 336 bytes
+    ICON = (
+        b'\x02'
+        b'`@'
+        b'?\xff\x11@\xfcB?\x1dB\x80z\x82B?\x1aA'
+        b'\x86A?\x18A\x88A?\t\xc0\x18\xc3\nA\x8aA'
+        b'\n\xc3=\xc5\x04N\x04\xc5?\x06\xc3\x02A\xcaA\x02'
+        b'\xc3?\x10A\xcaA?\x08\xcb\x02A\xc3@\x1eD\xc3'
+        b'\x80\xfc\x81\x02\xcc9\xcb\x01\x81\xc4D\xc4\x81\x01\xcc?'
+        b'\x06\x81\xcc\x81?\x0f\xc3\x01\x81\xcc\x81\x01\xc3?\x06\xc5'
+        b'\x04\x8e\x04\xc5=\xc3\t\x81\xc0z\xcc\x81\t@\x18C'
+        b'?\x07\x81\xcc\x81?\x12\x81\xce\x81?\x11\x81\xce\x81?'
+        b'\x11\x81\xce\x81?\x11\x81\xce\x81?\x11\x81\xce\x81?\x11'
+        b'\x81\xce\x81?\x11\x81\xce\x81?\x10\x81\xd0\x81?\x0f\x81'
+        b'\xd0\x81?\x0f\x92?\x0f\x81\x80\x81\x90\xc0\xfc\xc1?\x0f'
+        b'\xc1\x90\xc1?\x0f\xc1\x90\xc1?\x0e\xc1\x92\xc1?\r\xc1'
+        b'\x92\xc1?\r\xc1\x92\xc1?\r\xc1\x92\xc1?\r\xc1\x92'
+        b'\xc1?\r\xc1\x92\xc1?\r\xc1\x92\xc1?\x0c\xc1\x94\xc1'
+        b'?\x0b\xd6?\x0b\xc1@zT\xc1?\x0b\xc1T\xc1?'
+        b'\x0b\xc1T\xc1?\x0b\xc1T\xc1?\n\xc1V\xc1?\t'
+        b'\xc1V\xc1?\t\xc1V\xc1?\t\xc1V\xc1?\t\xc1'
+        b'V\xc1?\t\xc1V\xc1?\t\xc1V\xc1?\x08\xda?'
+        b'\x07\xc1\x98\xc1?\x07\xc1\x98\xc1?\x07\xc1\x98\xc1?\x07'
+        b'\xc1\x98\xc1?\x07\xc1\x98\xc1?\x06\xc1\x9a\xc1?\x05\xc1'
+        b'\x9a\xc1?\x05\xc1\x9a\xc1?\x05\xdc?\xff\x04'
+    )
+
+
+    def __init__(self):
+        self._checkbox = wasp.widgets.Checkbox(10, 45, "Enable beacon")
+        self._slider_current = wasp.widgets.Slider(4, 10, 110, 0x27e4)
+        self._slider_wait_time = wasp.widgets.Slider(8, 10, 180)
+        self._reg_enable = 0x00 # off, 800ms, part of 12.5mA
+        self._reg_pdriver = 0x2e #0x4e # part of 12.5mA, PON=1, magic
+
+    def foreground(self):
+        wasp.system.bar.clock = True
+        self._draw()
+        wasp.system.request_event(wasp.EventMask.TOUCH)
+
+    def _draw(self):
+        draw = wasp.watch.drawable
+        draw.fill()
+        wasp.system.bar.draw()
+        self._checkbox.draw()
+        draw.string("Intensity:", 10, 85)
+        self._slider_current.draw()
+        draw.string("Frequency:", 10, 155)
+        self._slider_wait_time.draw()
+        self._update()
+
+    def touch(self, event):
+        updated = self._checkbox.touch(event)
+        if event[2] >= 180:
+            updated |= self._slider_wait_time.touch(event)
+        elif event[2] >= 110:
+            updated |= self._slider_current.touch(event)
+        self._update()
+        if updated:
+            if self._checkbox.state:
+                self._enable_led()
+            else:
+                self._disable_led()
+
+    def _update(self):
+        wasp.system.bar.update()
+        self._checkbox.update()
+        self._slider_current.update()
+        self._slider_wait_time.update()
+
+        # Draw a dashed line representing intensity and frequency
+        # with thickness and separation of dashes
+        draw = wasp.watch.drawable
+        draw.fill(None, 10, 220, 227, 20)
+        x = 10
+        while x < 220:
+            wasp.watch.drawable.fill(0x27e4, x, 227, 8, (self._slider_current.value + 1) * 3)
+            x += (8 - self._slider_wait_time.value) * 8
+
+    def _enable_led(self):
+        self._reg_enable |= _ENABLE_HEN
+        if self._slider_current.value % 2:
+            self._reg_pdriver |= _PDRIVER_PDRIVE0
+        else:
+            self._reg_pdriver &= ~_PDRIVER_PDRIVE0
+        if self._slider_current.value >> 1:
+            self._reg_enable |= _ENABLE_PDRIVE1
+        else:
+            self._reg_enable &= ~_ENABLE_PDRIVE1
+        self._reg_enable = (self._reg_enable & (~_ENABLE_HWT)) | (self._slider_wait_time.value << 4)
+        wasp.watch.hrs.write_reg(_PDRIVER, self._reg_pdriver)
+        #print("writing PDRIVER={:08b}".format(self._reg_pdriver))
+        wasp.watch.hrs.write_reg(_ENABLE, self._reg_enable)
+        #print("writing ENABLE={:08b}".format(self._reg_enable))
+
+    def _disable_led(self):
+        self._reg_enable &= ~_ENABLE_HEN
+        wasp.watch.hrs.write_reg(_ENABLE, self._reg_enable)
+        #print("writing ENABLE={:08b}".format(self._reg_enable))
diff --git a/docs/apps.rst b/docs/apps.rst
index 0ee4272..75140bc 100644
--- a/docs/apps.rst
+++ b/docs/apps.rst
@@ -45,6 +45,8 @@ Applications
 
 .. automodule:: apps.alarm
 
+.. automodule:: Beacon
+
 .. automodule:: apps.calc
 
 .. automodule:: apps.demo
diff --git a/res/BeaconApp.png b/res/BeaconApp.png
new file mode 100644
index 0000000..8fc4754
Binary files /dev/null and b/res/BeaconApp.png differ
diff --git a/res/beacon_icon.png b/res/beacon_icon.png
new file mode 100644
index 0000000..4bd99f9
Binary files /dev/null and b/res/beacon_icon.png differ