Usually, we know that the phone signal is good or bad with the step icon of the status bar. Well, on Android phones, with tripartite tools or a lot of personalized ROM, the presentation of the signal has a colorful format.
However, to check the signal strength scientifically between different mobile phones, the most intuitive and accurate way is to look at the dBm (one milliwatt decibels) and asu (alone signal unit).
Android native places this data in a SIM card state. Of course, some of China’s ROM entrance will be different. There are also some extremely geeky friends want to replace the signal icon in the status bar with DBM values by using CM, MIUI and other systems.
Because each manufacturer has a different definition of the number of corresponding signal grid numbers, dBm can be considered as a more accurate horizontal comparison method.
XDA Dev reports that the latest version of the Android Open Source Project shows that Google will allow carriers to hide signal strength in the future.
However, this adjustment does not shut down the API from the bottom, which means the three-way APP can still be obtained, such as Wi-Fi analyzer, LTE Discovery, etc.
Due to appear lately, XDA tends to think that this feature will be enabled on Android 9.0 next year.
Note: generally speaking, when DBM >= -90, asu>=10 signal is normal.