The new ESP32 comes as a major upgrade to the popular ESP8266, having new important features, but also downsides. Despite it offers allot of new functions like Bluetooth and integrated sensors (Temperature, Touch, Pulse, Hall) the costs remains under 15$. But this does't means that it can simply replace the ESP8266. In order to see if its a good invest for your project, you first need to know the goods and the bads.
I have worked hard to write a very complex and thorough article which you can read here:
ESP32 module review and programming tutorial
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