The Particle Argon is an IoT development board that allows you to connect your mesh network to Wi-Fi. With the Nordic nRF52840 SoC and an ESP32 you have all the power of an ARM Cortex M4 with OpenThread mesh networking, Wi-Fi (b/g/n), NFC, plenty of GPIOs, LiPo charging and more. The board is designed to act as a standalone Wi-Fi endpoint or a Wi-Fi enabled gateway for a Particle Mesh network.
The Argon is also configured in the popular Feather footprint making it also compatible with Feather Shields! That means it includes a JST connector for a LiPo battery as well as charging of the battery over USB. Particle also provides an RGB status LED and a JTAG (SWD) connector for debugging and an onboard PCB antenna for your mesh network (you will need a U.FL antenna for NFC or Wi-Fi)
The Argon comes with access to the Device Cloud (10 free micro networks available) as well as three free months of device Cloud access using a cellular gateway. The Particle Could has some great features for building connected projects, including over-the-air firmware updates, and easy-to-use REST API, and firmware development supported by web and local IDEs.