Learned it too late. I was new to Smart Plugs and didn't know the "intricacies" of using these. The Tapo App will make the Smart Plugs available therein become offline when the WiFi (Wireless Router) and Internet (ISP's Modem) is turned off. Those two are required for these plugs to function. After exiting the Tapo App and running it back again without Internet and WiFi, it will ask the user to log in to the TP-Link Cloud before being given access. This means the Tapo smart plugs DO NOT HAVE a LAN Control Mode unlike those low-cost Sonoff switches using an old eWelink App.

@RendCycle 

Good day,

Thank you very much for your time and patience.

Sorry for the delay.

Tapo plugs have a LAN control mode;

And it would work with a router when the internet is not available or disconnected, but the Wi-Fi signal needs to be enabled for the plug all the time;

So which means, if the Tapo plug and mobile phone are connected to the same wireless network, but the Wi-Fi did not have an access to internet;

You could still control the plug on the smartphone;

 But once the smartphone used 4G data, you would not be able to control the plug;

Thanks a lot.

@Brook Thanks for the reply. But nope, this does NOT work for me. Tested it several times. As soon as the Internet goes down (Just the Modem is turned off but WiFi Router is still turned on), it takes only a few seconds for the Tapo App to indicate "Unstable Network". All the plugs reflected in the app then disappear. When I exit the Tapo App and try to run it again, I will be asked to log in into the TP-Link Cloud. All Tapo plugs (P100 & P105) are in a single network and turned on but they are NOT accessible through the Tapo App through just WiFi. The plugs all have the latest firmware version.

Maybe TP-Link can showcase this feature actually working on a video and/or have some clear tutorial/guide on how to properly set up these plugs to work through WiFI only (if it really works) because I think this is one of the most important feature a customer will be looking for.  Including the "LAN Control" feature in the specifications info and/or on marketing collaterals for the plugs would also help clarify the existence of said function. The capability to be managed even only through WiFi was what I was expecting how these plugs would work and so far, I only noticed Sonoff actually indicating "LAN Control" feature on their products as a major thing.

I hope the existence of this feature can be clarified because I'm worried that all the Tapo Plugs I'm using might have factory defect then.