Signal Radar · Offline SOS AI
Catches the signal you can't
Only for iPhone
$4.99 · Designed for iPhone. Not verified for macOS.
iPhone
We hope you never need this app. We built it for the moment you do.
THE PROBLEM YOU CAN'T SEE
In the backcountry, signal doesn't come back gracefully. It flickers — appears for half a second, vanishes, returns ninety seconds later for a second and a half, gone again. You can't catch it. Your hands are frozen, your phone is on your hip, the window closes before you can open your messages.
Signal Radar's only job is to catch that window. It runs silently in the background, 24/7, scanning cellular for the tiniest flicker of reconnection. The instant signal returns — even for a fraction of a second — a pre-composed email fires to your trusted contacts: GPS coordinates, altitude, timestamp, and any custom message. Locked screen, dead-tired, or unconscious — it still works.
WHEN THE SIGNAL ISN'T COMING BACK
Sometimes you're not waiting for rescue. You're waiting for yourself. Snake bite. Broken bone. Burned hand. Hypothermia setting in. What do you do in the next sixty seconds?
We packed Gemma 4 — Google's on-device LLM — directly into the app. Photograph a snake, the model identifies it across 50 venomous species worldwide and walks you through first aid. Photograph a sting, it identifies 40 bees / scorpions / spiders / marine toxins. Type "deep cut, my own thigh" — it talks you through pressure points, tourniquet thresholds, when to release. CPR, severe bleeding, lightning, hypothermia, heat stroke, burns, getting lost — every scenario, illustrated, on-device, zero internet. Apple Vision plus feature-vector matching drops cross-category errors to near zero.
GLOBAL EMERGENCY HOTLINES · 100+ COUNTRIES
Police, fire, ambulance, coast guard, fraud, consular protection — exact digits, no guessing. Say "chest pain" and the medical line surfaces. Cross a border and the local hotlines load instantly.
PRIVACY-FIRST
No backend. No analytics. No cloud. Your location, signal history, and chat data stay on your device. We literally can't see them.
THE PROMISE
We genuinely hope this sits unused on your phone for years. But if the day comes — the night your foot slides off the trail, the moment the dust storm rolls in, the second your boat takes water — we want Signal Radar to be the one light still on. Built for the day you hope never comes.
Ratings & Reviews
We have fixed some bugs.
The developer, 海峰 程, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Linked to You
The following data may be collected but it is not linked to your identity:
- Location
- Usage Data
- Diagnostics
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- 海峰 程
- Size
- 121 MB
- Category
- Utilities
- Compatibility
Requires iOS 16.0 or later.
- iPhone
Requires iOS 16.0 or later. - Mac
Requires macOS 13.0 or later and a Mac with Apple M1 chip or later.
- iPhone
- Location
- This app may use your location even when it isn’t open, which can decrease device battery life.
- Languages
- English
- Age Rating
16+
- 16+
- Contains
Unrestricted Web Access
- Copyright
- © 2026 NOVAHALO.AI
