M5Stack M5StickC PLUS ESP32-PICO Mini IoT Development Kit BLE 4.2 WiFi DIY 4060137066009 | eBay
Picoclick C3T IoT button from makermoekoe on Tindie
DIY Pocket Size Emergency Button Notifier for Elderly With WiFi -- Personal Alarm (IoT) : 3 Steps (with Pictures) - Instructables
WiFi Button | Hackaday.io
DIY Dashbutton for the Internet of Things : 6 Steps (with Pictures) - Instructables
Add a "physical" Smart Button To Your Next Project - DEV Community
GitHub - garthvh/esp8266button: An IoT Dash Like Button using an esp8266, a push button and GitHub Actions. Tested on an Adafruit Huzzah, SparkFun Thing, and Wemos D1 Mini