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You can set your phone to use mobile data automatically when the connection to the Wi-Fi network is weak. To turn automatic use of mobile data on or off, you need to turn on mobile data.
1. Find "Wi-Fi Assistant"
Press Wi-Fi Assistant.
2. Turn automatic use of mobile data on or off
Press the indicator next to "Intelligently Select the Best Wi-Fi" to turn on the function.
Press the indicator next to "Switch to Mobile Automatically " to turn the function on or off.
3. Return to the home screen
Press the Home key to return to the home screen.