Home / Primary Watch Zone
Know what's happening where it matters.
Your Primary Watch Zone gives you a clear status in seconds — and one practical answer to "Am I good right now?"
TestFlight Soon
TerraSignal
Calm, clear alerts for the places you care about.
Built around one practical question: "Am I good right now?"
Monitor earthquakes near home, family, travel spots, and saved Watch Zones — with clear color-coded status, trusted data sources, and alerts that respect your attention.
No account required
Optional location access
Watch Zone alerts
USGS + EMSC data
The Problem
Most alert apps give you too much noise — or not enough context.
An earthquake notification should not leave you wondering.
"Was that near me?"
"Is my family's area okay?"
"Was it offshore?"
"Was it strong enough to care about?"
"Is there a tsunami advisory?"
The Answer
Am I good right now?TerraSignal is built around one practical question. Not a noisy global feed. Not fear. Not disaster porn. Just calm situational awareness for the places that matter to you — fast, clearly, without the noise.
The App
See your zones. Understand the signal.
Watch Zones
Monitor home, family, travel, and coastal areas.
Create Watch Zones for the places you want TerraSignal to watch. Set a region, an alert radius, and a magnitude threshold — then keep an eye on them all from one screen.
Seismic Map
Explore recent seismic activity worldwide.
Filter by magnitude, time, source, and Watch Zone events. Toggle hazard layers as they come online — tsunami, fault lines, volcanoes, plate boundaries, NOAA bulletins.
Event Detail
Understand each event quickly.
Magnitude, depth, distance, advisory status, reliability, and source links from public seismic agencies — clearly presented. Tap a dot, peek the card, dive into the full detail when you need it.
Alerts
Alerts that respect your attention.
Choose your threshold and get notified only when it matters. Watch Zone alerts, optional global alerts, quiet hours, and a critical-alerts bypass for major events.
Trust & Privacy
Built on trusted seismic data.
USGS, EMSC, and tsunami advisory sources where available — auto-selected by region, or take manual control. No account required. Your data stays on your device.
Character Personality
A little personality — tuned to the magnitude.
An optional in-app animated character moves with the energy of each event. In-app only: Apple's notification rules keep system banners serious, so character motion lives inside TerraSignal when you open an alert.
Eighteen screens, one calm signal layer. Join the TestFlight →
Alert System
Simple colors. Clear control.
Green, yellow, orange, and red make it easy to understand what changed — without reading a technical earthquake feed.
Minor
Low-level activity. Nothing requiring immediate attention in your Watch Zone.
Recent Activity
Noticeable or relevant activity. Worth a glance — but no cause for concern yet.
Stay Aware
Increased activity worth monitoring. Stay informed and check for advisories.
Critical
Major event or urgent condition near a Watch Zone. Clear, calm, immediate signal.
Your Control
Alerts that respect your attention.
TerraSignal alerts are built around your saved Watch Zones — not random global noise. You choose the threshold. You stay in control of what gets your attention.
Optional settings include quiet hours, critical overrides, aftershock grouping, and notification style preferences. The app adapts to how you want to be informed.
For major events and tsunami warnings, TerraSignal shifts into serious mode automatically — regardless of your quiet settings.
M3.5+
Active Alerts
Noticeable activity
Active
M4.5+
Elevated Alerts
Worth monitoring
Elevated
M5.5+
Strong Alerts
Widely felt events
Strong
M6.0+
Critical Alerts
Major or urgent
Critical
Planned Expansion Areas
Built for more than earthquakes.
Planned
Tsunami Advisories
Planned
Volcanic Activity
Planned
Fire Warnings
Planned
High-Wind & Storm
Planned
Hurricane Awareness
Planned
Tornado Alerts
Earthquakes first. More hazard layers later. TerraSignal starts with earthquake monitoring. Future hazard layers will be added only when they are reliable enough to ship.
One calm signal layer for the places you care about.
Trusted Data
Built on trusted seismic data.
USGS
U.S. Geological Survey
The primary source for earthquake data across the United States and global monitoring networks.
EMSC
Euro-Mediterranean Seismological Centre
Real-time seismological data across Europe, the Mediterranean, and surrounding regions.
NOAA
Tsunami Warning Sources
Tsunami advisory data where available, integrated into Watch Zone critical alert states.
Private by design. TerraSignal does not require an account. Location access is optional — create Watch Zones manually or by dropping a pin. Your alert preferences are used to provide the service, not to sell your data. Diagnostics, if enabled, help improve reliability and are not linked to your identity. Data sourced from USGS, EMSC, and tsunami advisory sources where available.
Privacy
Privacy Policy
How we handle your data. No account required. No data selling. Plain and simple.
Read Privacy Policy →
Terms
Terms of Use
The rules for using TerraSignal — direct, readable, and 18 sections clear.
Read Terms of Use →
FAQ
Common Questions
Alerts, Watch Zones, data sources, colors, pricing, and more — answered simply.
Read FAQ →Pricing
Start free. Upgrade when you want more coverage.
Free
TerraSignal
During TestFlight, selected Pro-style features may be temporarily unlocked for testing.
- Know you're good — right where you live.
- 1 Watch Zone
- Earthquake activity dashboard
- Standard magnitude alerts
- Map & recent activity
- Optional location-based distance
Pro
TerraSignal Pro
During TestFlight, Pro features are being tested and accessed.
- Watch every place — and person — you care about.
- Multiple Watch Zones — home, family, travel, coast
- Custom alert radius per zone
- Enhanced alert controls & thresholds
- Critical alert overrides & quiet hours
- Advanced map & data-source features
- Severe-weather hazard alerts as they roll out
Free during early testing. Pro pricing finalized after tester feedback.
Try TerraSignal Pro
Severe-weather hazard alerts — tornado, fire weather, flooding and more — are in preview now and rolling out during beta.
Early Access
Know what's happening where it matters.
TerraSignal helps you monitor earthquakes and emerging hazards around your most important places — clearly, calmly, and without unnecessary noise.
Join the TestFlight and help shape what ships.
TerraSignal is an informational monitoring tool and is not an official emergency warning system. Always follow instructions from local authorities and official emergency agencies during any hazard event.