I²C smartWiFi Smart Device
Selecting WiFi and MCU
One major criteria is power consumption.
Albeit popular, the ESP8266 requires too much power, up to 400 mA. Additionally, it is poorly documented and lacks WiFi stability.
More advanced radios, like the CC3100 or WINC1500 radios, or all-in-one CC3200 MCU, offer a better power management and a more stable WiFi connection.