Amazon's WiFi Button is way way better than the ESP8266: it has 1MBit internal flash, 16MBit external flash, a powerful 120MHz microcontroller with tons of peripherals (2 DACs, 3 ADCs, etc), an internal MEMS microphone (!)

The microcontroller on Amazon's button also has a real 1500-page documentation in English, instead of 10-page badly translated Chinese datasheet.