My personal experience: After reinforced presence of mold in the kitchen I have some time before the device - very inexpensive - acquired. Only küzrlich I have another kitchen wall, which had already recognized many times mold, again renovate / refurbish need. Thanks to this device, I immediately was able to determine where the risk particularly of moisture places this wall, and have obtained obvious results, could not find the alleged causes, so I assume that I - after appropriate measures - a renewed mold growth at these sites shall never be saved. I was so in good conscience continue to renovate / finish.
The very small, handy, easy, practical and, above all, inexpensive device was a big help for me.
I can therefore only recommend.
The little "rounder" but can the like more than just the moisture in plaster measure: if you change the mode, you can therefore measure wood. In another mode, even the (air) temperature!
The operation is simple: just use the button to switch on the device. Longer Pressing and holding the button allows you to switch to another mode, you dan then by change by pressing the button once briefly (the one wiederhaolt then, until you are in the "right" mode). - So is really convenient "foolproof".
By "Einpieken" the metal "Measuring tiller" in the object to be measured (wood, plaster, or similar) is then obtained immediate results.
Whether the small, lightweight and above all quite cheap cell phones would really satisfy "professional" claims, as the name implies ("ProfiScale"), I can not say; but I'm assuming that the values given are correct; because that seemed more realistic to me.
My expectations the device has so far more than fulfilled.
Therefore: I can only recommend!