I bought it for €14, which is a good price. The top part has an incline (good for viewing the watch or phone on it), with a rubber "brake" (after removing the protective plastic). The adjustment buttons are inside the plastic base (which also provides the incline), making it difficult to imagine how you can adjust the alarm clock or turn it off without removing the plastic base. The only external button is an on/off button, which stops the alarm or turns off the clock (desirable, as it doesn't have brightness adjustment and it shines too much at night). The warm ambient light on the base can be adjusted by tapping the surface (off/mid/high). Inside, there is a 3-position switch for off/ambient/color. When charging a phone, the base turns blue. If there is poor contact, or when it is fully charged, or at unknown times, the blue light dims and other colors start flashing (red, green). Sometimes, if you remove the phone, the last color remains. I haven't found anywhere, in manuals or from the manufacturer or in comments abroad, what these colors mean and how to control them! It's probably just a gimmick.

Now, about charging: With a Samsung Galaxy and a ClearView case, it plays games, turns on, and then loses connection. With good aim and luck, it may succeed in charging and maintaining the charge. Without the case, it is almost stable. With a fast charger, I see 9V 1A. And just when you think it's going to reach 100%, sometimes it starts flashing green rapidly and stops, and the flashes continue even if you remove the phone. You have to unplug it to make it stop. Overall, it doesn't inspire confidence to "leave the phone on it and charge," especially with a case.

As a final note, I don't like that I can't use it with a phone case without any worries (other wireless chargers claim to work up to a distance of 10mm...), the clock has too much light for the night, and the colors are inexplicable (I recommend keeping the switch off for bedside use)! It's obvious that with the phone on top, it covers most of the clock (which may be good since it shines too much at night). It's worth noting that some reports abroad mention that the charging stopped working after 1-2 months.

However, it doesn't seem to waste energy (after charging its built-in battery) and it doesn't heat up. For bedside use, turn the clock off (using the button on top) if it bothers you, tap for ambient light (I believe the clock's light is already sufficient, useful if the clock is off), and charge the phone without a case (preferably without flashy colors).

These are my observations after one week of use.

Edit Oct 1, 2022:
I noticed that although it initially seems to not work with a case, it flashes and appears to not make "contact," if you leave it on top and wait a few minutes (with good "aim"), it eventually starts charging. It seems that the Qi protocol negotiates the best conditions (and rejects the possibility of FOD) and eventually achieves a 5-10W charging condition (despite occasional interruptions with the case, it generally charges). [Link to Qi wireless charging standard article]

Also, I decoded the colors: when the power supply of the base is connected or disconnected (via microUSB), the RGB lights flash in a circular pattern once as an indication.

I bought it for 15€ and I was not satisfied at all from the beginning. It charges for 2 seconds and then stops, and then the same thing happens again. I tested it on a Samsung S8+ and on a Xiaomi

I have it for about 1 month, it charges the iPhone 11 normally without any problem. Overall, it is nice with its lighting, which I have disabled. It also shows the time. It charges the phone even with the Spigen case, which is quite thick.