The Alfonce Remote Gateway is a Companion Computer for drone, but it can also be used standalone. It includes Mavlink proxy, a media server to stream video, a controller for cameras and some computer vision scripts includes
It has several conexion management included : Serial connexion to Pixhawk (could be used with other flight controller), Wifi client and hotspot 4G LTE dongle Virtual Private Network client (Open VPN) HTTP Connexions
You'll find anything you're looking for the use of th Alfonce Remote Gateway