With smartphones being our constant digital companions, it’s no surprise they’ve also become prime targets for malicious activity. One of the growing concerns for many users is whether their phone is being tracked — either by hackers, suspicious apps, or even someone close to them. Fortunately, there are hidden USSD and MMI codes you can dial to investigate unusual activity, detect forwarding or tracking, and regain control of your privacy.
In this comprehensive guide, we’ll explore what these codes are, how they work, and how you can use them to protect yourself from unauthorized surveillance. Whether you’re using Android or iPhone, this article covers everything you need to know.
What Does It Mean If Your Phone Is Being Tracked?
Before diving into the codes, it’s crucial to understand what “tracking” really means. Phone tracking refers to the unauthorized monitoring or spying on your device. This could include:
- Monitoring your call logs or messages
- Tracking your physical location via GPS
- Recording audio without consent
- Watching your screen activity
- Redirecting your calls and messages
Such actions could be carried out by spyware, hidden apps, or even people with access to your phone. The key is that they happen without your knowledge or permission, making it a serious breach of privacy.
The Most Common Signs Your Phone Is Being Tracked
Recognizing early warning signs can help you act before too much data is compromised. Look out for:
- Excessive battery drain even when the phone is idle
- Overheating when you’re not using any intensive apps
- Weird background noises during phone calls
- Unusual data usage, particularly when you’re not browsing
- Sluggish performance and sudden app crashes
- Delayed shutdowns or reboots
- Strange messages with code-like symbols
If you notice several of these red flags, your device might be under surveillance. That’s when the codes we’ll explore next become your best line of defense.
USSD & MMI Codes: The Basics
Unstructured Supplementary Service Data (USSD) and Man-Machine Interface (MMI) codes are hidden commands that allow users to communicate directly with their phone’s operating system or carrier network.
Some of these codes can provide insight into whether someone has tampered with your device settings, especially call forwarding or tracking features. Let’s go over the most valuable ones.
*#21# – See if Calls or Data Are Being Diverted
Dialing *#21# on your phone shows whether any of your calls, SMS, or data are being forwarded to another number.
- What it reveals: If your voice calls, data, fax, or SMS are being unconditionally forwarded.
- Why it matters: Someone tracking your phone might use call forwarding to redirect your communication without your knowledge.
If the code shows that none of these features are active, your phone is likely not being tracked this way. If anything is active, especially to an unfamiliar number, it’s a serious red flag.
*#62# – Check Call Forwarding When Your Phone Is Off or Unreachable
This code reveals what happens when your phone is powered off, has no signal, or is in airplane mode.
- What it reveals: Numbers that receive your calls and messages when your phone is unreachable.
- Why it matters: Hackers can redirect your communication during network outages to collect private info.
Again, if you see numbers you don’t recognize, it’s time to dig deeper and consider contacting your carrier or resetting your call forwarding settings.
*#67# – Forwarding When You’re Busy
This code tells you whether your phone is set to forward calls when it’s busy or you’re already on another call.
- What it reveals: Any number that intercepts your calls if your line is occupied.
- Why it matters: A compromised line might redirect calls to a different number where conversations are recorded.
It’s especially useful for professionals who are on the phone frequently. Always double-check the forwarding numbers.
*#61# – Forwarding When You Don’t Answer
Similar to *#67#, this code tells you what happens when you don’t answer a call.
- What it reveals: Numbers where calls are forwarded after your phone rings and goes unanswered.
- Why it matters: Spies or stalkers might set this up to monitor when you’re away from your phone.
*#004# – The All-In-One Forwarding Check
This is a convenient code that gives you a full overview of your conditional call forwarding settings.
- What it reveals: Forwarding when busy, unreachable, or unanswered—all in one go.
- Why it matters: Saves time by showing everything in a single screen.
If anything looks suspicious, it’s a strong indicator that your phone may have been tampered with.
##002# – The Ultimate Reset Code
Worried after seeing suspicious numbers? Dial ##002# to instantly cancel all call forwarding.
- What it does: Resets all types of call redirection.
- Why it matters: This is your go-to defense move to block all third-party monitoring via call forwarding.
Use this after any suspicious activity to restore your phone’s normal settings.
Android Secret Menu: *#*#4636#*#*
This Android-specific code gives you access to an advanced diagnostic menu.
- What it includes:
- Phone information
- Battery statistics
- Usage history
- Wi-Fi and mobile data metrics
Look for anything odd in your app activity, like apps using your network at weird hours or draining the battery in the background.
iPhone Secret Code: 3001#12345#
If you’re an iPhone user, entering 3001#12345# opens Field Test Mode.
- What it includes:
- Signal strength (in dBm)
- Tower location data
- Detailed network info
While it doesn’t directly reveal spyware, odd network patterns could indicate tampering or unauthorized data routing.
What to Do If You Discover Suspicious Activity
If any of the codes above reveal call forwarding or data activity you didn’t authorize, take the following actions immediately:
- Reset call settings using ##002#.
- Run a trusted antivirus scan. For Android, consider Bitdefender or Malwarebytes. For iPhone, check battery and data usage per app.
- Change all passwords, especially Apple ID, Google Account, banking apps, and social media.
- Perform a factory reset after backing up your important data.
- Contact your mobile carrier for additional help and verification.
- Enable two-factor authentication for extra account security.
Preventing Future Tracking or Surveillance
The best way to combat tracking is to prevent it in the first place. Here’s how:
- Use strong PINs or biometrics on your phone.
- Avoid jailbreaking or rooting your device—it weakens your security layers.
- Review app permissions regularly, especially for location, microphone, and camera.
- Download apps only from official stores like Google Play or the App Store.
- Use VPNs and encrypted messaging like Signal or ProtonMail for sensitive communication.
- Enable Find My Device features with secure access credentials.
- Never leave your phone unattended in public or unfamiliar places.
Read More: Piso WiFi 10.0.0.1 Pause Time, Login, Logout – Complete User Guide 2025
Final Thoughts: Take Control of Your Privacy
Using the right codes to see if your phone is being tracked is a powerful tool in the modern era of digital surveillance. These simple commands can unveil hidden forwarding settings or uncover potential spyware activity. However, the most critical part is your awareness and action. If something feels off — trust your instincts, investigate with these codes, and act quickly.
Your phone is a gateway to your digital life — protect it like you would your home or wallet. In a world where privacy is constantly under threat, being informed is your best line of defense.
