The X-NUCLEO-IDW04A1 Wi-Fi evaluation board is based on the SPWF04SA module and expands the STM32 Nucleo portfolio. The SPWF04SA module has an embedded STM32 MCU, a low-power Wi-Fi b/g/n SoC with integrated power amplifier and power management, and an SMD antenna. The SPWF04SA module relies on 2 MB MCU internal Flash. 1 MB of the internal Flash is for storing the user file system and to perform secure firmware update over the air (FOTA). A hardware interface allows the use of external memory to extend file system storage capability with no size limit. The firmware includes a complete IP stack, dynamic web pages with SSI to interact with the module and a REST API (get & post) for conveniently transferring files to and from servers in the cloud. The module can simultaneously behave as a socket server and socket client. The firmware supports secure sockets with TLS encryption, ensuring secure end-to-end communications with the cloud. The X-NUCLEO-IDW04A1 interfaces with the MCU on the STM32 Nucleo board via the UART serial port and SPI interface.