The charging speed of the mobile phone is related to the charging head and the charging cable. Charging speed will be fast. Try to use the original charging cable to charge the device. Because the power of the plug is not enough, the charging speed will be slow. Most of the time, the 1A AC adapter is smaller than the 2A AC adapter, so we can usually judge the current size according to the size of the adapter. However, using a high-power iPad plug to charge the iPhone, Apple officials say it is no problem. Charging cable, although the USB cable on the market is the same, in fact, the current they support is not the same. The local voltage, the input and output voltage of the plug, and the voltage of the phone itself, all have a certain relationship with the speed of charging the phone.