As the B738 Zibo Mod is a Freeware Airplane, it offers great functions, for example the built in and modified AviTab. Within this Tablet you can modify the Aircrafts look, e.g. the Winglets or Antennas. Also the modified Aircraft offers much more functions than the Default 737-800. You can download the Aircraft here. I downloaded the livery on the image from here.
The Zibo Team greatly integrated the AviTab into the Aircraft, beneath the normal functions of the Tablet, which are moving maps, a PDF-Viewer, and much more, you can play Passenger Announcments in different languages, you can adjust the planes fuel and payload, also you can change the sounds volume or save aircraft states. As already mentioned you can change the planes look, like no Winglets, normal Winglets and split Winglets, a HUD for the Captain and much more.
The Aircraft features a GPU (Ground Power Unit), an ASU (Air Start Unit), De-Icing Trucks and custom Airstairs. It also has an improved FMC, which is much better than the default one.
To come to a conclusion, you can clearly say that the 737-800X from Zibo shows a large improvment in comparison to the Default 737-800. Mainly because it has much more features than the Default one AND it is Freeware!