The main function is the same for all humidifiers - to raise the humidity level in a room - and a regular one does the job just as well as a smart version. If your goal is just to get rid of dry skin and mucous membranes, then an expensive gadget with an app is money wasted. A regular mechanical or electric humidifier works on a simple principle: it evaporates water, humidity rises, problem solved. The sensor in a smart model doesn't even add any functionality - it just shows you the humidity level, which you can already feel from your skin and how you generally feel.
A smart humidifier only makes sense if you want automation: like, the device turns itself on and off when it reaches the right humidity level, or you can control it remotely from your phone. But do you really need that? At work you'll turn the thing on in the morning and forget about it until evening - no app needed. At home even less so: the device sits in a corner, evaporates water, that's it.
My advice: get a regular humidifier in the mid-price range with basic power adjustment. It'll last you a long time, your skin will get back to normal, and you can spend the money you save on something actually useful. Smart features are convenient for people who actually use them, not just pay for them.