The ELA Smart Hub is one powerful device. Not only is it a light bulb, and a Wi-Fi repeater, but it also serves as the main communication hub for the ELA Smart Network. You can connect up to 80 ELA products to one Hub. Even with such a high number of devices, the ELA Smart Network will remain stable when in operation.
Other ELA products have smart capabilities like the ELA Smart Hub, however it does not emit its own Wi-Fi, it only receives commands from the ELA Smart Hub. Therefore, you need the ELA Smart Hub in order to control other ELA products.