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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"
2. Turn on Wi-Fi
Press the indicator next to "Wi-Fi" to turn on the function.
3. Turn automatic use of mobile data on or off
Press Wi-Fi assistant.
Press the indicator next to "Select best networks automatically" to turn the function on or off.
If you turn on the function, press the indicator next to "Ask permission for using mobile data".
Press Got it.
4. Return to the home screen
Press the Home key to return to the home screen.