Few years ago CityBus has Free wi-fi by Zain. But that didn’t last long. It turned out that that was only a promotion from Zain.
Good thing CityBus is now offering the same on board. Now you can connect to the internet for free whenever you’re traveling. So far I’ve seen only bus number 999 traveling from Kuwait City to Fahaheel who has this on board free wifi. I’ve also seen the same for KGL buses number 21.