*#06# - Displays your iPhone IMEI Code.
*3001#12345#* and press call - Enter Field Mode. Information about the SIM-card, indicators of cellular communication and signal level. All data is constantly updated.
*777# and press call - Account balance for prepaid iPhone.
*225# and press call - Bill Balance. (Postpaid only)
*646# and press call - Check minutes. (Postpaid only). It will display you the available minutes of your talk time.
*#30# and press call - Calling line presentation check ...
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Apple iPhone XS - secret codes