After 5G network is commercialized, the 4G phones will still function normally. The 5G phones allows for interoperability with 4G/3G/2G network. Therefore, 5G phones work with 4G network, as same as 4G phones work with 3G network .
Read moreHow can I upgrade my phone to 5G?
Go to Settings > Cellular > Cellular Data Options . If you see this screen, your device has 5G activated. If you don’t see this screen, contact your carrier to confirm that your plan supports 5G. Turn on Airplane Mode, then turn it off.
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