The Kraang Communication Orb is a device, found by April during the episode Operation: Break Out, is a large orb that picks up all of the Kraang's communications. Having it captured, the turtles use it to listen in on the Kraang's plans.
In Newtralized! the netralizer uses the orb to get information from the Kraang Walker shipping.
In Plan 10 Raphael uses the technodrome communication orb to contact his brothers