After starting, on the main screen, you will see the tapnum categories for which you can find information, for example, information about the operating system, the operation of the central processor, the state of the battery and its voltage with temperature, the operation of the sensor display, and the like. The amount of data will be really huge, so it will take a long time to study.
The interface itself is made in a minimalist design in the style of Material Design, therefore, there are only the necessary elements in a competent location. There are useful tabs in the settings where you can change display units, refresh rate, and so on. Use the received data to optimize and eliminate errors in the phone.