All cell phones have a unique IMEI number. The number can be located form phone settings but for a shortcut, just type #06# to view it onscreen.
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The call barring facility allows you to block both incoming and outgoing calls on your phone. Call barring is a paid facility but just in case you have it enabled on your phone plan, then hers a code to activate the facility immediately without having to search for it. Enter *33*PIN# to enable the facility and again #33*PIN# to disable it. These are among the coolest codes hidden in your iPhone to improve functionality.
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Did you know that when you send an SMS, it isn’t sent directly to the person receiving your message? Instead it is routed through a message center using a different phone number. This secret number can be viewed onscreen by typing in *#5005*7672# and then press the ‘call’ button.
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