1. Check IMEI (* # 06 #)
IMEI – International Mobile Equipment Identity (device identification number) consists of 15 digits that confirm the iPhone exists on the mobile network. The IMEI is always printed on the iPhone box and is especially necessary to report to the police, insurance in case the iOS device is lost or stolen. Instead of going to Settings> General> About to check your IMEI, you can use the code * # 06 #.
2. Field Test (* 3001 # 12345 # *)
Field Test is a feature that displays cellular signals and reads data around mobile towers. When using this code, in the upper left corner you will see a negative number right next to the mobile network name. Numbers near -50 are considered optimal while around -120 is very bad. You can press this number to switch between number display and signal graphs.
In addition, in Field Test window, there are many information such as SIM Info (SIM information), UMTS Cell Environment (UMTS coverage area), GSM Cell Environment (GSM coverage area), …
3. Block outgoing calls | Check: * # 33 # | On: * 33 * pin # | Off: # 33 * pin #
Call barring is a solution to avoid accidental calls when you give the phone to children to play. You can turn on Airplane Mode to disable mobile networks, but this mode can easily turn off. A better way is to block all outgoing calls using the command * 33 * PIN # where PIN is the SIM PIN code in use, not the PIN used to access the phone. To turn off this feature, use the command # 33 * PIN #.
To be able to use the call blocking feature, go to Settings> Phone, activate SIM PIN, enter the PIN in the blank box (the default is usually 1111 or 1234). A very important note is that the SIM PIN is only entered three times, and if you enter the wrong SIM you will be locked. In case you forget your SIM PIN, you need to call or visit the operator directly to check.
After completing activation of SIM PIN, use * # 33 # to check the status of outgoing calls (outgoing calls), mobile data usage (Data usage), messages (Messages), etc. If the returned result is Disabled, the call blocking feature has not been activated, you can now enter * 33 * PIN # to activate.
4. Call waiting | Check: * # 43 # | On: * 43 # | Off: # 43 #
Call Waiting feature will help others in standby until you end the conversation. You will receive an audio notification when another call is waiting and the option to reject or hold the phone until the conversation is complete. In iOS, you can activate call waiting by going to Settings> Phone> Call Waiting or faster by entering * 43 #.
5. Diverting calls
When you’re busy at work, or traveling away, you can divert the call to another phone or ask a relative to take the call through the Call Forwarding feature. On iOS go to Settings> Phone> Call Forwarding and set the forwarding phone number. Or you can use * # 21 # to check the status of the redirects; * # 62 # (check for incoming calls); * # 67 # (calls when the phone is busy) and ## 002 # to disable call forwarding.
6. Hide the dialed number | Check out: * # 31 #
If you don’t want other people to know your number, you can add # 31 # to the outgoing phone number. In case you want to hide the number in all outgoing calls, go to Settings> Phone> Show My Caller ID.
How much do you know with these commands or syntax? !! If you have any good ways and syntax on iphone, please share it below the article for me to add.
