ESP32-1Button-BLE-Keyboard.ino

#include <BleKeyboard.h> // https://github.com/T-vK/ESP32-BLE-Keyboard

BleKeyboard bleKeyboard;

bool pressing = false;

void setup() {
  pinMode(25, INPUT_PULLUP); // A1 pin
  bleKeyboard.begin();
}

void loop() {
  if (bleKeyboard.isConnected()) {
    if (digitalRead(25) == LOW && !pressing) {
      pressing = true;
      bleKeyboard.press(KEY_LEFT_GUI);
      bleKeyboard.press('d');
    }

    if (digitalRead(25) == HIGH && pressing) {
      pressing = false;
      bleKeyboard.releaseAll();
    }
  }
}