Smartphones have plenty of settings and apps these days, so the chances are that you can change everything you want to, monitor everything you need to, but that is not always the case.

Going all the way back to feature phones, there have been some settings that require a little noise in order to find, with phone software keeping some settings hidden from most users with technicians and tinkerers able to delve more deeply into the software and how it works. Accessing these settings, or sometimes, even simple status displays requires the entry of what have become known as secret USSD codes, and if you know them, the world is your oyster.

Secret-iPhone-codes

We have already shown you in the past how to get into some of the deeper and darker settings hidden within some Android phones, but what about the iPhone? Are there some that are specific to Apple’s smartphone, and more importantly, how do you access them? Well, we’re going to tell you.

All of these USSD codes need to be entered via the Phone app, and require the input of a handful of digits and characters followed by a tap on the call button. It’s not difficult, but do be careful; sometimes, messing around with these things can cause some serious problems down the line. You’ve been warned.

Now, with that out of the way, here are the codes you’re going to need!

*3001#12345#* – Activate Field Mode, which contains all of your iPhone’s more technical settings. It also converts the signal bars into an actual number.

*#5005*7672# – Check SMS center

*646# (Postpaid only) – Display your available minutes

*225# (Postpaid only) – Check your current bill’s balance

*#31# – Choose whether to hide your number

*3370# – Enable or disable EFR (Enhanced Full Rate), which improves your iPhone’s voice quality, but will quite likely reduce battery life

*#21# – Check call forwarding status

*777# (Prepaid only) – To check the account balance

*#62# – Check which number calls will be forwarded to if no service is available

*#76# – Check connecting line presentation

*#67# – Check the number to be used for call forwarding

*#33# – Check whether anything is barred, such as international calling etc.

*#61# – Check number of missed calls

*#06# – Displays your iPhone’s IMEI number

*#43# – Check call waiting status

*43# – Activate waiting

#43# – Deactivate call waiting

Field-Test-USSD

We’re sure that will be enough to keep you entertained tonight. Don’t go changing settings unless you know what you’re doing, though!

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