Comparison

G3 Alarm vs Magnetic Sensor

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

G3 Alarm

This app allows you to control and monitor a GSM/SMS alarm system remotely. Arm or disarm your system, receive alerts, and adjust settings via your smartphone. It's designed for easy installation and use with a focus on security.

Highlights
  • Remote arm/disarm
  • Receive intrusion alerts
  • Adjust system settings
  • Voice memo recording
  • Listen-in functionality
  • Control via phone call/SMS
Read full description

Chuango G3 GSM/SMS Alarm System Chuango G3 is an elegantly powerful alarm system that is easy to install and use. All it needs is a regular working 2G SIM card, and it can be armed/disarmed via a phone call or SMS text message from preauthorized phone numbers; preauthorized remote controls; or smartphone app commands. Upon detection of intrusion, the G3 will sound the built-in siren and call and/or text out to you for appropriate action. The intuitively designed Chuango G3 app interface enables you to effortlessly adjust system settings on the go: arm/disarm, home mode, remote voice memo or listening in

About

Magnetic Sensor

Features
Read full description

Magnetic Sensor turns your phone's built-in magnetometer into three precise tools: • Compass — A live, tilt-compensated compass with cardinal direction (N/E/S/W) and adjustable magnetic declination so the needle points to true north, not just magnetic north. • Metal Detector — Set a baseline reading anywhere, choose Low/Med/High sensitivity, and feel haptic pulses that get stronger as the field deviates. Perfect for finding studs in a wall, screws under drywall, or rebar in concrete. • Field Logger — Record samples at up to 60 Hz, then export to CSV via the share sheet. Saved recordings stay in the app for replay or re-export. KEY FEATURES • Live X / Y / Z axis readings + total field magnitude • Tilt-compensated heading using the accelerometer • Magnitude history sparkline + multi-channel chart • Rolling statistics: mean, standard deviation, RMS, range • Figure-8 calibration helper with quality indicator • Min / Max tracking with one-tap reset • Three sample rates: Slow (500 ms), Normal (100 ms), Fast (16 ms) • Light / Dark / System theme • English and Korean • Unit options: μT, mGauss, nT • Adjustable smoothing • Magnetic declination presets • Haptic alerts for the detector • Keep-screen-awake while recording • CSV export with full timestamp + per-axis data PRIVACY All sensor data is processed on-device and never leaves your phone. The app does not collect location, contacts, or personal information. Anonymous mobile advertising is used to keep the app free; you can watch a rewarded ad to unlock unlimited CSV sharing for the session. WHO IT'S FOR • Hobbyists exploring magnetic fields • DIYers detecting screws, studs, and rebar • Students collecting data for physics or geology projects • Hikers wanting a reliable phone compass • Anyone curious about the invisible field around them REQUIREMENTS A device with a magnetometer (most phones built since ~2013). The app cannot work on devices without one — it will tell you on launch.

Screenshots

G3 Alarm4 screens
Magnetic Sensor4 screens

Verdict

The call

The clearest difference is ads: G3 Alarm at none against Magnetic Sensor's shown. G3 Alarm also leads on iOS requirement (7.0 vs 15.1). Magnetic Sensor's advantage is update cadence (fortnightly vs every 3 months). On price, in-app purchases and device support there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

UpkeepUpdate frequency

G3 Alarm ships an update every 3 months, Magnetic Sensor fortnightly. The most recent releases landed on November 1, 2026 and October 31, 2026 respectively.

Scorecard3 real differences · 7 level
G3 Alarm versus Magnetic Sensor: the parameters behind the verdict, then further details
ParameterG3 AlarmMagnetic Sensor
PriceFreeFree
Rating5.0 (1 ratings) — better—
Positive reviews66.7% of reviews—
Number of ratings1 — better—
Update frequencyEvery 3 monthsFortnightly — better
AdsNo — betterYes
In-app purchasesNoNo
MonetizationFree—
DevicesiPhone, iPodiPhone, iPod
Requires iOS7.0 — better15.1
Further details — not scored
Size57 MB25 MB
Age rating4+4+
DeveloperChuango Security Technology CorporationSeonggon Sim

In-app purchases

None

G3 Alarm

No in-app purchases

None

Magnetic Sensor

No in-app purchases

Questions

Is G3 Alarm free?
G3 Alarm is free to download, with no in-app purchases.
Is Magnetic Sensor free?
Magnetic Sensor is free to download, with no in-app purchases.
Do G3 Alarm or Magnetic Sensor have ads?
Magnetic Sensor shows ads; G3 Alarm does not.
Which is updated more often, G3 Alarm or Magnetic Sensor?
G3 Alarm ships an update every 3 months, and Magnetic Sensor fortnightly. Most recently, G3 Alarm was updated on November 1, 2026 and Magnetic Sensor on October 31, 2026.

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