


With Apple and Android rolling out new models and updates faster than we can keep up with, it sometimes feels like we've only just got to grips with our latest handset before we're splashing out on the next model.
Apple keeps things slightly more consistent thanks to its yearly release of the next iPhone and the new simplified iOS naming system, but with 2025 revealing the standard model, higher-priced iPhone 17 Pro and 17 Pro Max, and the iPhone Air, we were spoiled for choice.
As phones continue to evolve at breakneck speed, even those who consider themselves the most tech-savvy can sometimes be left feeling like they're relics from a bygone era. If you want to keep yourself up to date and down with the kids, PC Mag has revealed a series of 'secret' codes that you might not know are lurking in the background of your iPhone and Android devices.

We're reminded that coders have a history of creating backdoors or Easter eggs that can only be accessed via a key.
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Not just restricted to programmers, the general public can gain access via Unstructured Supplementary Service Data (USSD), which is also referred to as 'quick codes' or 'feature codes'. Although initially created for Global System for Mobile Communications phones on the 2G network, it can still be found on modern 4G and 5G phones.
There are apparently around 800 Man Machine Interface (MMI) codes for specific devices, with users able to unlock them through the simple use of their keypads. Allowing you to directly communicate with a service provider's computers, we'll admit that most of these codes are pretty useless for everyday use. After all, how often have you needed to know how nearby cell towers are performing?
Remembering that many codes don't cross over with carriers, the outlet suggests you do an internet search for your device's make and carrier, as well as "USSD" or "MMI" for an accurate list. Still, try punching in the following codes and see what happens.
Typing in this code and pressing the call button will grant you insight into 'Field Mode', which effectively gives you the rundown on local networks and cell towers. The reason this one is useful is thanks to it revealing your signal strength.
If you've ever tried to sell your phone, you'll likely need an IMEI number. This unique sequence links your phone to a specific number and can also confirm whether a device has been blacklisted.
If you're trying to get some much-needed R&R but want to check where your calls are being forwarded to, it's always best to double-check.
Although different on different carriers, *#43# deactivates call waiting on AT&T.

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As 646 spells out 'MIN' on a keypad, it's no surprise that this lets you know how many minutes you have left. Handy if you aren't on an unlimited plan.
If you're known for forgetting when your monthly bill is coming out, 3282 (spelling 'DATA') will reveal how long your current cycle is and what your usage levels are.
There could be any number of reasons you want to block caller ID, but this is especially for use on landlines, with blocking Caller ID typically requiring you to phone customer service.
With complaints about receiving government alerts, you can silence the end of the world by calling *5005*25370#.
Similar to checking out your billing cycle, dial *777# on a prepaid phone to get a text about how much you've got left.
Specifically for Android users, this one brings up a testing panel with the likes of 5G/LTE debugging info, usage stats, and Wi-Fi information. We'll admit we don't understand much of it.
To completely shut out the world, call barring blocks all incoming and outgoing calls. Still, you'll need to know the PIN number for your SIM or eSIM card to activate it.
If you want to check out all the legal jargon and regulatory information about your phone, simply type *#07#. iPhone users can find this under Settings > General > Legal & Regulatory.
We'd avoid trying to test this one, as the above code reportedly performs a full factory reset on your Android, even going as far as reinstalling a device's original firmware.