# Seismograph: Vibration Log — Shake Meter · MMI · Waveform > Real-time vibration waveform recorder and earthquake detector using iPhone accelerometer. (iPhone/iPad app by Kyu-Hee Jang.) - Source: https://appshunter.io/ios/app/seismograph-vibration-log/id6761254708 (this page in markdown: same URL + `.md`) - Developer: [Kyu-Hee Jang](https://appshunter.io/developer/1587578867) - Category: Utilities, Productivity - Price: Free - Rating: 5.00/5 from 2 App Store ratings - Age rating: 17+ - Requires: iOS 16.4 · 61 MB - Languages: American English - Released: 2026-03-31 - Data updated: 2026-08-18 - Monetization: ad-supported - User reviews in markdown: https://appshunter.io/ios/app/seismograph-vibration-log/id6761254708/reviews.md ## What is Seismograph? Turn your iPhone into a vibration recorder: live 3-axis waveform, automatic capture of shaking events, and a log you can replay and export. HOW IT MEASURES Shaking is read from the accelerometer and reported as peak ground acceleration, then mapped to the Modified Mercalli Intensity scale (MMI I-XII) using the USGS ShakeMap relationship. MMI is the primary scale because it is the one a phone can honestly produce — it describes how strongly a place shook. A magnitude-style number is shown alongside as a rough estimate; it is not a Richter measurement, which needs a calibrated instrument and the distance to the epicentre. AUTOMATIC CAPTURE Leave the app open and the phone resting on a solid surface. When shaking persists past the trigger threshold the app records the waveform, timestamps it, and files it in the event log with its peak acceleration and MMI level. Brief knocks and picking the phone up no longer create events. Monitoring runs while the app is open — including while you read other tabs — and holds the screen awake while the alarm is armed. iOS does not let an app like this listen in the background, so it cannot watch while the phone is locked or while you use other apps. It is a monitoring station you set down, not a background alarm. WHAT YOU GET • Live 3-axis waveform with three sensitivity presets • Event log with waveform replay • Peak acceleration and MMI for every event • On-screen alarm with vibration for stronger events, while monitoring • CSV export per event, or the whole log • Recent earthquakes feed for context PLACEMENT MATTERS Rest the phone on a table or floor. An accelerometer cannot tell ground motion from the motion of a hand carrying it — that is why real seismometers are anchored to the ground. WHO USES IT Anyone curious how much a passing train, washing machine or construction site actually shakes a building · people in seismic areas who want a record of what they felt · physics and earth-science teaching Available in 25 languages. ## Key features - Real-time 3-axis seismograph waveform - Richter and Mercalli scale estimation - Automatic vibration event detection - Waveform recording and playback - CSV data export - Vibration alert notifications ## Frequently asked questions about Seismograph ### Does Seismograph have ads? Yes, Seismograph contains advertisements. As a free utility app, it relies on ads to support its development and operation. ### What devices does Seismograph support? Seismograph is compatible with iPhone and iPod devices. It leverages the accelerometer hardware present on these devices for its functionality. ### How accurate is Seismograph's earthquake estimation? Seismograph provides Richter and Mercalli (MMI) scale estimations based on recorded vibration data. While it functions like a professional seismograph, it's important to note that these estimations are derived from your device's accelerometer and may not be as precise as dedicated scientific instruments. ### Can I save and analyze the vibration data from Seismograph? Yes, Seismograph allows you to record waveforms and export the data in CSV format. This enables you to save and analyze vibration patterns for further study or documentation. ### What is the age rating for Seismograph? Seismograph has an age rating of 17+. This rating is typically assigned based on content that may be considered mature or complex, though the app's core functionality is educational and monitoring-based. ### How often is Seismograph updated? The latest version of Seismograph is 1.0.13, which was last updated on June 18, 2026. Updates typically address bug fixes, performance improvements, and potential new features. ### What are the different sensitivity levels in Seismograph? Seismograph offers three sensitivity levels: micro, normal, and strong. These levels allow you to adjust the app's detection threshold based on the expected intensity of vibrations you wish to monitor. ### Does Seismograph notify me of vibrations? Yes, Seismograph provides vibration alert notifications. This feature ensures you are promptly informed of detected vibration spikes, allowing for timely review of the recorded data. ## Version history (last 5 releases) ### 1.0.27 — 2026-08-14 Opening a captured event now counts as reviewing it, and sharing evidence completes cleanly. Both were previously treated as nothing happening, which is also why the app only ever recognised a CSV export as finishing something. Startup was reworked too: the launch screen no longer waits on work it does not need before showing you the meter. ### 1.0.26 — 2026-08-12 Two fixes that change whether this app works at all. Monitoring used to stop the moment you looked at another tab, and again when the screen switched off — so leaving the phone on the table to catch shaking recorded nothing. Detection now keeps running while the app is open, whichever tab you are on, and the screen stays awake while the alarm is armed. Picking the phone up used to log an event. The trigger now needs shaking to persist rather than spike, which means a knock on the desk or lifting the phone no longer files a fake earthquake — while genuine shaking from 1 to 8 Hz still captures. That range was checked against simulated waveforms, not assumed. Also in this update: • No more full-screen ad after a passively recorded event. An ad for doing nothing was never a fair trade; it now appears only when you export. • The listing no longer claims "vibration alert notifications". There are none, and there never were — the alarm is an on-screen banner with vibration, and only while you are monitoring. The description now says so, along with the fact that the phone has to be resting on something solid: an accelerometer cannot tell ground motion from the motion of your hand. • The magnitude number is now described as the rough estimate it is. Richter magnitude needs a calibrated instrument and the distance to the epicentre; MMI, which describes how strongly your location shook, is the scale a phone can honestly report. ### 1.0.25 — 2026-08-06 Ads no longer interrupt you mid-task. Anything full-screen now waits until you have finished what you were doing, and the app stops showing a blank pause where an ad failed to load. ### 1.0.24 — 2026-08-05 New App Store screenshots that show the app as it really looks, plus fixes to what those screens were getting wrong. ### 1.0.23 — 2026-08-03 Thanks for using our app! This update brings behind-the-scenes performance and stability improvements for a smoother, more reliable experience. Your support means the world to us. ## More apps by Kyu-Hee Jang - [Calculator+ Tip Tax BMI Unit](https://appshunter.io/ios/app/calculator-plus-tip-tax-bmi-unit/id1587591476) - [QR Lens+ Barcode Scanner Pro](https://appshunter.io/ios/app/qr-lens-plus-barcode-scanner-pro/id1590631012) - [Sound Noise Meter+ dB SPL](https://appshunter.io/ios/app/sound-noise-meter-plus-db-spl/id1593197145) - [Tremor Vibration Meter](https://appshunter.io/ios/app/tremor-vibration-meter/id6759666731) - [Lux Light Meter - Luminance](https://appshunter.io/ios/app/lux-light-meter-luminance/id6759858193) - [Barometer: Air Pressure](https://appshunter.io/ios/app/barometer-air-pressure/id6759883097) All apps by Kyu-Hee Jang: https://appshunter.io/developer/1587578867 ## Related topics [pocket seismograph](https://appshunter.io/ios/topics/pocket-seismograph) · [seismograph app for vibration detection](https://appshunter.io/ios/topics/seismograph-app-for-vibration-detection) · [seismograph](https://appshunter.io/ios/topics/seismograph) --- *Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-08-18.*