The "Nexa Bridge X" is a Smart Home bridge device. The internal name is "Bridge2".
There is now also the Bridge3, which seems like it's mostly the same as Bridge2 except it has a separate adapter for Z-Wave!
It can be attached to a home network and monitor / control devices via an App/Cloud or Local Web UI. Supports assigning devices to rooms and various automations via the provided firmware.
Since this devices comes with a (semi) open API and Websocket it's custom to create custom integrations.