Product Introduction: 1. The battery tester is an application assistant specially designed for car battery batteries. It is a practical application, users can check the real-time voltage of the car battery and other related information through the mobile phone in real time. 2. It can monitor the voltage of the car's starting system and charging system in real time, helping users to fully understand the data and characteristics of the car battery. 3. Transfer data to your mobile phone via Bluetooth and enter the app to view it in real time. Android operation method: Open the mobile phone settings-Bluetooth-select the pairing app, enter the app after the connection is successful, click the setting icon in the upper right corner, search for the app in the device management to connect, and test after the connection is successful. iOS operation method: Open the mobile phone settings-After confirming that Bluetooth is turned on, go directly to the app and click the setting icon in the upper