SeismoSense

100% free personal seismograph. Background monitoring, audible alerts, privacy-first. No purchases, no subscription, no ads.

SeismoSense turns your iPhone into a personal seismograph — detecting ground motion at your exact location, entirely on-device, while you sleep.

100% FREE. No In-App Purchases. No Subscription. No Ads.

PRIVACY-FIRST DETECTION All processing happens on your iPhone. No data is ever sent to external servers. Your seismic log stays on your device — always.

HOW IT WORKS SeismoSense uses the STA/LTA (Short-Term Average / Long-Term Average) algorithm — the same trigger method used in professional seismic networks worldwide — to continuously scan your accelerometer. When ground motion exceeds the detection threshold, the app logs the event with:

• Estimated intensity (MMI scale: I through XII)
• GPS coordinates (stored on-device only)
• Duration and detection confidence score
• P-wave and S-wave component breakdown
• Dominant frequency analysis

KEY FEATURES — ALL FREE

• Real-time seismic waveform display
• Background overnight monitoring (screen off)
• Active Monitoring Zone with live map
• Unlimited event history
• Adjustable sensitivity: Conservative / Balanced / Sensitive
• Time-sensitive notifications that break through Focus mode
• Audible alarm even when iPhone is in silent mode
• Apple Sign In or Guest mode — no account required
• Full Turkish and English localization

DISCLAIMER SeismoSense is a personal utility app. It is NOT an official earthquake warning system. It is NOT connected to government seismic networks (USGS, AFAD, JMA, Kandilli). Do NOT use for life-safety decisions. Always follow official emergency services and government alerts.