For Android Go to the Settings app > About phone > Status > SIM status > Signal Strength . You will see numbers expressed in dBm (decibel milliwatts).
Read moreHow do you check the signal strength of multiple carriers?
Android Field Test Mode You simply need to find your way to “Settings” > “About Phone” , and your numerical signal strength will be available under either Network or Status, depending on the model of the phone you own.
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