ANTI-SPY SCANNER

MARKAROV DEV

About this app

ANTI-SPY SCANNER shows the radio traffic around you and helps you find where it comes from. Two things people use it for: finding something of their own that is lost, and noticing something that is not theirs.

FOUR CHANNELS, ONE LIST

- Bluetooth LE — tracker tags, watches, sensors, earbuds. Several updates per second, the only genuinely fast channel.
- Bluetooth pairing mode — headsets and speakers that are waiting to be paired.
- Wi-Fi — access points with band, channel and security. Where the access point supports 802.11mc, the distance is a real time-of-flight measurement.
- Cellular — the serving tower and its neighbours, across 2G, 3G, LTE and 5G.

Each channel is one button, always on screen, showing how many sources it can hear right now. A channel you switch off is not scanned at all, which saves battery rather than just hiding rows.

FINDING TAGS ARE MARKED

Apple Find My, Google Find My Device and Tile publish the signatures their tags broadcast, so those get a red dot in the list — no guessing involved. A red dot means "this is a tracker", not "you are being followed": your own tag and a stranger's look identical from outside.

HUNT — WHAT TELLS THE DIFFERENCE

A hidden tag does not betray itself by being loud. It betrays itself by still being there after you have moved. The hunt flags a device that has been around for more than eight minutes, across more than 250 metres of travel, heard in at least three separate places. It can keep watching with the screen off.

RADAR

Point the phone and walk. A bearing held steady by the compass and gyroscope, a distance estimate, and a ping that speeds up as you close in — the motion detector from the films, and you can search without looking at the screen.

MAP

Every measurement is placed where you were standing, so you get a real coverage map over OpenStreetMap: one colour per channel, brightness by signal strength. Tap anything to see what it is. Measurements of the same device from different places are combined to estimate where the source actually is.

HIDDEN CAMERAS

Two techniques that do not involve radio at all: a magnetometer for the magnet a covert camera is usually stuck to, and the phone camera for the infrared illuminator a night-capable lens turns on in the dark, which the sensor sees and your eye does not.

HONEST ABOUT LIMITS

A phone cannot measure the angle of a Bluetooth signal — no phone can, it needs an antenna array. Direction is derived from how the signal changes as you turn, because your body shadows 2.4 GHz, so you have to turn around slowly. Distance from signal strength is an estimate, not a measurement. Android allows four Wi-Fi scans per two minutes and one Bluetooth inquiry cycle per fifteen seconds. The app tells you all of this where it matters instead of pretending otherwise.

PERMISSIONS

Location is required because Android withholds Bluetooth and Wi-Fi scan results from apps that do not hold it. The app never asks for coordinates in order to know where you are — it uses them to draw the coverage map and to tell whether something is travelling with you, and they never leave the phone.

The internet is used in exactly one place: downloading map tiles from OpenStreetMap. Nothing about what the scanner found is ever sent anywhere. The map sheet can be switched off, after which the app makes no network requests at all. No analytics, no advertising, no third-party libraries.

Interface in English and Russian, following your phone's language.

What’s new

The usage counter can now be switched on: the toggle used to be hidden because the build carried no keys. It stays off by default. The text now lists honestly what is sent when you do switch it on: the screen name, the fact and kind of a started scan, and a random installation number. Scan results are never transmitted.