How to Detect Hidden Camera With Mobile Phone [2024 Guide]

Most places in the world have laws against hiding a camera to record someone without their permission when they expect to be alone. It’s a serious crime that requires serious punishment. So you must be careful about the hidden camera, especially in hotels, changing rooms, and other places requiring privacy.

It can be a surprise, but a smartphone can easily locate and identify hidden cameras and listening devices. It means you don’t need specialized hidden camera detectors. These methods are tested and proven to detect a hidden camera. All the methods listed below might not work perfectly in every situation because, with the innovation of technology, hidden cameras have become better at deceiving.

What does a hidden camera look like?

A tiny hidden camera | Kichigin VIA Canva

Hidden cameras don’t look like normal surveillance cameras. They’re far more manageable in size. They can usually be placed in an area equal to the space between your thumb and forefinger. These tiny cameras typically have a diameter of one to two inches.

Hidden cameras are more likely to be custom-built than store-bought because it’s easier to hide them when they’re made to fit exactly into the desired location. If the camera is not wireless, its wire, circuit board, and other components will most likely be exposed, revealing its location.

Since most hidden cameras require constant power, it is typically installed into existing electrical equipment, such as a wall outlet, smoke alarm, or alarm clock. Finding a hidden wireless camera is difficult as it has no extra components that can be traced. Your smartphone can be helpful in this regard.

Using a phone camera to detect light

Smartphone cameras can detect infrared light that the human eye can’t. If you’re concerned about hidden cameras, you can quickly check the area with your smartphone’s camera.

Most of the hidden cameras, like regular remotes, give off infrared light that the camera can pick up on a smartphone. Infrared sensors are standard on most smartphone cameras. Thus while you’re scanning the room, the red light will be captured by both your front and rear cameras. The infrared light will appear as a blinking pinpoint when your phone’s camera aligns with the hidden one. The procedure is as follows:

  1. Open the camera on your mobile device
  2. Turn off the lights. The room should be completely dark for the phone’s camera to function properly.
  3. Aim the camera in the direction you suspect the hidden cameras are located. In our case, we used a second mobile phone to demonstrate the method. The camera of the first mobile phone detected the call sensor also know as proximity sensor present on the second mobile with a blinking red light, as shown below. (Call and other sensors on mobile usually work by emitting Infrared sensors).

You’ll see a blue or red light in the dark if there is a hidden camera. Check the area around a light that may or may not be blinking. There are strong chances that you’ll find the hidden camera in that area. Keep in mind that this method will only work in case of the camera has an IR sensor.

Use your phone’s flashlight

Lenses have a natural tendency to reflect light when they are exposed to it. This characteristic of lenses can be utilized to detect hidden cameras. To spot hidden cameras, one can turn on your smartphone’s flashlight and flash it around the room while being close to objects.

The hidden camera lens is typically small in size, and its reflection will also be relatively small. Therefore, to detect them, one needs to be close. To spot hidden cameras, it is advisable to check objects such as smoke detectors, electrical outlets, power strips, wall hangings, clocks, clothes hooks, etc.

Check your network

If you want to know if there is a live camera in the room but the IR method doesn’t work, you can check what other devices are connected to the network. Start with your phone’s built-in network scanner (Wi-Fi detection).

  1. Launch the Settings app and navigate to the Network & Internet section.
  2. Tap to Wi-Fi.
  3. Move your mobile device around while monitoring the list of local Wi-Fi networks.
Check the Wi-Fi list to find a suspicious network

A concealed camera may be in the area if your phone identifies an unusual network or a connection name with camera brand names.

Use a network analyzer app

Several network analyzer apps are available to determine which gadgets are linked to a specific network. These programs can scan for and produce a list of all the devices connected to your network, allowing you to verify which ones you recognize and so facilitating the detection of unwanted visitors. Here are some of the popular Android apps that you can download to detect a hidden camera: 

Here are some of the iOS spycam detector apps: 

Use a phone call to detect interference

A surveillance camera’s radio waves can cause interference in a phone call. During a call, you can experience crackling, buzzing, or general signal interference if you get your phone within a few centimeters of a live camera.

You can use this method to spot a hidden camera by calling a friend and keeping them on the line while you move the phone around the room. Place the call on speaker and get the phone near any potentially harmful device. An increase in interference suggests a possible covert camera is located there.

Remember that this isn’t a foolproof approach either, as not all cameras produce radio waves, and your phone can fail to detect interference, even if a camera is there.

Use an app to detect magnetic fields

Using a magnetometer or an app that uses your phone’s compass to detect magnetic fields can be helpful when trying to find lost electronic gadgets in reality.

Magnetometer, available for free in the iPhone App Store, provides a live readout of magnetic field strength. There may be just 15–20 microteslas of magnetic energy in a room free of electronic devices, but this might vastly increase when an iPhone is brought near a camera.

Magnetometer app for iOS

If you own an Android device and want to detect magnetic fields, you can get Detectify from the Play Store for free. A magnetometer will indicate a high reading when put near steel, other ferrous metals, and any electrical device.

Detectify app for Android

Since the intensity detected will vary from phone to phone, you should instead watch for increases in the result as you move the phone about rather than a fixed number of microteslas.

While it is helpful to utilize technology to scan for the presence of unknown radio frequency devices and then follow up with a magnetometer sweep, it is still necessary to use your eyes and, in some cases, lay hands on an item to determine if there is indeed a spy camera.

What to do if you detect a hidden camera?

If you have discovered a hidden camera around you, here are things that you should do without wasting time:

  • Take photographs of the camera, its placement, wiring, and any other important details. It is recommended, however, that the camera remains in its current location.
  • The best action is to call the police or contact the authorities and explain what’s happening.
  • To report a hotel’s secret camera, guests must speak with a front desk staff member. 

Final Verdict

It’s against the law to secretly film someone without their knowledge, and it’s not easy to spot a hidden camera. Using a smartphone to detect infrared light, searching the local network for suspicious gadgets, making a phone call to detect interference, and utilizing an app to detect magnetic fields are just some of the methods suggested in the article for finding concealed cameras.

These techniques aren’t perfect, but they can help you find hidden cameras. If a hidden camera is found, the finder must notify the proper authorities promptly.


Kamil Anwar

Kamil is a certified MCITP, CCNA (W), CCNA (S) and a former British Computer Society Member with over 9 years of experience Configuring, Deploying and Managing Switches, Firewalls and Domain Controllers also an old-school still active on FreeNode.