The health of a mobile phone can be simply understood as its capacity. For example, when you first came out, you bought this mobile phone. The battery is 4000 mAh, and your health has dropped to 80, so the battery capacity has dropped to 3200 mAh, and the capacity will also decrease. As long as this capacity does not drop below 80, its battery life will not be too big, and it will drop to 60~80.
Batteries are consumables. You can't expect it to be in good condition all the time, and its health will decline rapidly after leaving the factory. It is a very fast process to drop from 100 to 90, but it is also a very difficult process to drop below 80. The old mobile phone I bought three years ago has been tested for health for more than two years, and it still remains at around 82. I wanted to change the battery, but the official maintenance staff said that your rated capacity was similar. Although a new battery can be replaced, the battery life will not be greatly improved.
The upgrading of mobile phones is very fast. From this technical experience, it is not recommended to buy a mobile phone with a price of 1000 yuan or even more than 5,000 yuan. Unless you say that you are financially fine and just want to experience the latest mobile phone, you don't have to think about it at all. From 2000 yuan to 3000 yuan, you can basically have the latest functions of mobile phones on the market now, and then those 2 ~ are quite complete.