diff --git a/README.md b/README.md
index d166c0c..d6e420b 100644
--- a/README.md
+++ b/README.md
@@ -6,7 +6,7 @@
 
 ![AIOArduino](https://cdn-learn.adafruit.com/assets/assets/000/057/496/original/adafruit_io_AIOA.png?1531335660)
 
-This library provides a simple device independent interface for interacting with [Adafruit IO](https://io.adafruit.com) using Arduino. It allows you to switch between WiFi (ESP8266, ESP32, AirLift, WINC1500, & WICED), Cellular (32u4 FONA), and Ethernet (Ethernet FeatherWing)
+This library provides a simple device independent interface for interacting with [Adafruit IO](https://io.adafruit.com) using Arduino. It allows you to switch between WiFi (ESP8266, ESP32, ESP32-S2, Airlift, WINC1500, & WICED), Cellular (32u4 FONA), and Ethernet (Ethernet FeatherWing).
 
 ## Documentation
 
diff --git a/examples/adafruitio_26_led_btn/adafruitio_26_led_btn.ino b/examples/adafruitio_26_led_btn/adafruitio_26_led_btn.ino
new file mode 100644
index 0000000..e4958ec
--- /dev/null
+++ b/examples/adafruitio_26_led_btn/adafruitio_26_led_btn.ino
@@ -0,0 +1,116 @@
+// Adafruit IO Publish & Subscribe, Digital Input and Output Example
+//
+// Adafruit invests time and resources providing this open source code.
+// Please support Adafruit and open source hardware by purchasing
+// products from Adafruit!
+//
+// Written by Todd Treece for Adafruit Industries
+// Modified by Brent Rubell for Adafruit Industries
+// Copyright (c) 2020 Adafruit Industries
+// Licensed under the MIT license.
+//
+// All text above must be included in any redistribution.
+
+/************************** Configuration ***********************************/
+
+// edit the config.h tab and enter your Adafruit IO credentials
+// and any additional configuration needed for WiFi, cellular,
+// or ethernet clients.
+#include "config.h"
+
+/************************ Example Starts Here *******************************/
+
+// Button Pin
+#define BUTTON_PIN 0
+
+// LED Pin
+#define LED_PIN LED_BUILTIN
+
+// button state
+bool btn_state = false;
+bool prv_btn_state = false;
+
+// set up the 'led' feed
+AdafruitIO_Feed *led = io.feed("led");
+
+// set up the 'button' feed
+AdafruitIO_Feed *button = io.feed("button");
+
+void setup() {
+
+  // set button pin as an input
+  pinMode(BUTTON_PIN, INPUT);
+
+  // set LED pin as an output
+  pinMode(LED_PIN, OUTPUT);
+
+  // start the serial connection
+  Serial.begin(115200);
+
+  // wait for serial monitor to open
+  while(! Serial);
+
+  Serial.print("Connecting to Adafruit IO");
+
+  // connect to io.adafruit.com
+  io.connect();
+
+  // set up a message handler for the count feed.
+  // the handleMessage function (defined below)
+  // will be called whenever a message is
+  // received from adafruit io.
+  led->onMessage(handleMessage);
+
+  // wait for a connection
+  while(io.status() < AIO_CONNECTED) {
+    Serial.print(".");
+    delay(500);
+  }
+
+  // we are connected
+  Serial.println();
+  Serial.println(io.statusText());
+  led->get();
+
+}
+
+void loop() {
+
+  // io.run(); is required for all sketches.
+  // it should always be present at the top of your loop
+  // function. it keeps the client connected to
+  // io.adafruit.com, and processes any incoming data.
+  io.run();
+
+  // grab the btn_state state of the button.
+  if(digitalRead(BUTTON_PIN) == LOW)
+    btn_state = false;
+  else
+    btn_state = true;
+
+  // return if the btn state hasn't changed
+  if(btn_state == prv_btn_state)
+    return;
+
+  // save the btn_state state to the 'button' feed on adafruit io
+  Serial.print("sending button -> "); Serial.println(btn_state);
+  button->save(btn_state);
+
+  // store last button state
+  prv_btn_state = btn_state;
+
+}
+
+// this function is called whenever a 'led' message
+// is received from Adafruit IO. it was attached to
+// the counter feed in the setup() function above.
+void handleMessage(AdafruitIO_Data *data) {
+  Serial.print("received <- ");
+
+  if(data->toPinLevel() == HIGH)
+    Serial.println("HIGH");
+  else
+    Serial.println("LOW");
+
+  digitalWrite(LED_PIN, data->toPinLevel());
+}
\ No newline at end of file
diff --git a/examples/adafruitio_26_led_btn/config.h b/examples/adafruitio_26_led_btn/config.h
new file mode 100644
index 0000000..7440cad
--- /dev/null
+++ b/examples/adafruitio_26_led_btn/config.h
@@ -0,0 +1,67 @@
+/************************ Adafruit IO Config *******************************/
+
+// visit io.adafruit.com if you need to create an account,
+// or if you need your Adafruit IO key.
+#define IO_USERNAME "your_username"
+#define IO_KEY "your_key"
+
+/******************************* WIFI **************************************/
+
+// the AdafruitIO_WiFi client will work with the following boards:
+//   - HUZZAH ESP8266 Breakout -> https://www.adafruit.com/products/2471
+//   - Feather HUZZAH ESP8266 -> https://www.adafruit.com/products/2821
+//   - Feather HUZZAH ESP32 -> https://www.adafruit.com/product/3405
+//   - Feather M0 WiFi -> https://www.adafruit.com/products/3010
+//   - Feather WICED -> https://www.adafruit.com/products/3056
+//   - Adafruit PyPortal -> https://www.adafruit.com/product/4116
+//   - Adafruit Metro M4 Express AirLift Lite ->
+//   https://www.adafruit.com/product/4000
+//   - Adafruit AirLift Breakout -> https://www.adafruit.com/product/4201
+
+#define WIFI_SSID "your_ssid"
+#define WIFI_PASS "your_pass"
+
+// uncomment the following line if you are using airlift
+//#define USE_AIRLIFT
+
+// uncomment the following line if you are using winc1500
+// #define USE_WINC1500
+
+// comment out the following lines if you are using fona or ethernet
+#include "AdafruitIO_WiFi.h"
+
+#if defined(USE_AIRLIFT) || defined(ADAFRUIT_METRO_M4_AIRLIFT_LITE) ||         \
+    defined(ADAFRUIT_PYPORTAL)
+// Configure the pins used for the ESP32 connection
+#if !defined(SPIWIFI_SS) // if the wifi definition isnt in the board variant
+// Don't change the names of these #define's! they match the variant ones
+#define SPIWIFI SPI
+#define SPIWIFI_SS 10  // Chip select pin
+#define SPIWIFI_ACK 9  // a.k.a BUSY or READY pin
+#define ESP32_RESETN 6 // Reset pin
+#define ESP32_GPIO0 -1 // Not connected
+#endif
+AdafruitIO_WiFi io(IO_USERNAME, IO_KEY, WIFI_SSID, WIFI_PASS, SPIWIFI_SS,
+                   SPIWIFI_ACK, ESP32_RESETN, ESP32_GPIO0, &SPIWIFI);
+#else
+AdafruitIO_WiFi io(IO_USERNAME, IO_KEY, WIFI_SSID, WIFI_PASS);
+#endif
+/******************************* FONA **************************************/
+
+// the AdafruitIO_FONA client will work with the following boards:
+//   - Feather 32u4 FONA -> https://www.adafruit.com/product/3027
+
+// uncomment the following two lines for 32u4 FONA,
+// and comment out the AdafruitIO_WiFi client in the WIFI section
+// #include "AdafruitIO_FONA.h"
+// AdafruitIO_FONA io(IO_USERNAME, IO_KEY);
+
+/**************************** ETHERNET ************************************/
+
+// the AdafruitIO_Ethernet client will work with the following boards:
+//   - Ethernet FeatherWing -> https://www.adafruit.com/products/3201
+
+// uncomment the following two lines for ethernet,
+// and comment out the AdafruitIO_WiFi client in the WIFI section
+// #include "AdafruitIO_Ethernet.h"
+// AdafruitIO_Ethernet io(IO_USERNAME, IO_KEY);
\ No newline at end of file
diff --git a/library.properties b/library.properties
index d10fb01..13a064e 100644
--- a/library.properties
+++ b/library.properties
@@ -1,9 +1,9 @@
 name=Adafruit IO Arduino
-version=4.0.0
+version=4.0.1
 author=Adafruit
 maintainer=Adafruit <adafruitio@adafruit.com>
 sentence=Arduino library to access Adafruit IO.
-paragraph=Arduino library to access Adafruit IO using the Adafruit AirLift, ESP8266, ESP32, M0 WINC1500, WICED, MKR1000, Ethernet, or FONA hardware.
+paragraph=Arduino library to access Adafruit IO using the Adafruit AirLift, ESP8266, ESP32, ESP32-S2, M0 WINC1500, WICED, MKR1000, Ethernet, or FONA hardware.
 category=Communication
 url=https://github.com/adafruit/Adafruit_IO_Arduino
 architectures=*