#31# “ph number”: Hides number in all outgoing calls which means the receiver will not be able to see who’s calling.
*#06#: This shows you the IMEI number of your phone
*#*#4636*#*#: Sows the WI-Fi signal, battery life and various information
*#*# 7780*#*#: Instantly returns to factory settings and deletes applications only. Be sure you want to do this first.
*#*#8351#*#*: Listen to a recording of your voice in the last 20 phone calls that you made. This was a truly amazing code.
*#0*#: General test mode which works on Android and grants access to a variety of phone operations.
*#61#: This code prompts a popup which tells you the time in which a call is forwarded to the message center. On iPhone it shows the same info as *#67#
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*#0011#: This opens the service menu for Samsung galaxy
*#*#4636#*#*: This opens a secret menu for your Motorola phone.
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Press *646# and this shows your available minutes but this usually works only for postpaid plans and works on Galaxy cell phones where you get the info as a message.
Just press *225# this may not work on your iPhone but it will work on your android which prompts a message to show you your current balance.
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