NERV Disaster Prevention 4+

All you need, in one app

Gehirn Inc.

    • 4.8 • 17 Ratings
    • Free
    • Offers In-App Purchases

iPhone Screenshots


The NERV Disaster Prevention App is a smartphone service that delivers earthquake, tsunami, volcanic eruption and emergency warnings, as well as provides weather-related disaster prevention information for flooding and landslides, optimised based on the user's current and registered locations.

The app was developed to help people living in or visiting an area where damage is expected to occur, to accurately assess the situation and make quick decisions and actions.

With information received directly through a leased line connected to the Japan Meteorological Agency, our proprietary technology enables the fastest information distribution in Japan.

▼ All the information you need, in one app

Get a wide range of disaster prevention information, including weather and typhoon forecasts, rain radar, earthquake, tsunami and volcanic eruption alerts, emergency weather warnings and landslide information, river information, and heavy rain risk notifications.

By interacting with the map on the screen, you can zoom in on your location or pan across the country and see the cloud cover, typhoon forecast areas, tsunami warning areas, or the scale and intensity of an earthquake.

① Providing users with the most appropriate disaster information

The home screen displays the information you need at the time and place you need it. When there’s an earthquake, the home screen will show you the latest information. If another type of warning or alert is issued while the earthquake is active, the app will sort them depending on the type, elapsed time and urgency, so you’ll always have the most important information at your fingertips.

② Push Notifications for Important Information

We send out different types of notifications depending on the device’s location, the type of information and level of urgency. If the information is not urgent, we send a silent notification as not to disturb the user. For more urgent situations where a disaster is time-sensitive, a ‘Critical Alert’ alerts the user to an imminent danger. Notifications like Earthquake Early Warnings (Alert level) and Tsunami Warnings will be forced to sound, even if the device is in Silent or Do Not Disturb modes.

Note: Critical Alerts will only be sent to users in the target area of the most urgent types of disasters. Users who have registered their location but are not in the target area will instead receive a normal notification.

※ In order to receive Critical Alerts, you need to set your location permissions to “Always Allow” and have Background App Refresh turned on. If you don’t want Critical Alerts, you can disable them from Settings.

③ Barrier-Free Design

We paid close attention when designing the app to ensure our information is accessible to everyone. We put a focus on accessibility, with colour schemes that are easy to distinguish for people with colour blindness, and use a font with large, clear letters so long bodies of text are easy to read.

▼ Supporters’ Club (In-App Purchase)

In order to keep doing what we do, we’re looking for supporters to help us cover the development and operational costs of the app. The Supporters’ Club is a voluntary membership scheme for those who want to give back to the NERV Disaster Prevention app, by contributing to its development with a monthly fee.

You can find out more information about the Supporters’ Club on our website.


Gehirn Inc. is an information security company. The security and privacy of our users is our highest priority. We take great care not to collect excessive amounts of information about our users through this application.

Your exact location is never known to us; all location information is first converted to an area code used by everyone in that area (like a zip code). The server also doesn’t store past area codes, so your movements cannot be tracked.

Learn more about your privacy on our website.

What’s New

Version 5.1.2

This update features the following improvements
- Real-Time Seismic Intensity is now displayed on the Earthquake Early Warning screen by default
- Improved Real-Time information updates while viewing the Earthquake Early Warning screen
- The map on the Earthquake Early Warning screen now shows a larger area around the current location
- Improved Shaking Detection algorithm
- Improved display of Tsunami Forecast areas
- Added a retry process in the event of a network error
- Fixed English Translation of certain Tsunami Information

[Recent updates from the Development Team]
We extend our heartfelt condolences to those affected by the Noto Peninsula Earthquake that occurred at the beginning of this year. We also solemnly remember those who lost their lives.

During the Noto Peninsula Earthquake, we weren't satisfied with the performance of our push notification delivery infrastructure, so we tripled the number of instances and quadrupled the memory allocation to each, ensuring notifications were sent out as quickly as possible. We also identified and rectified minor issues in the Strong Motion Monitor layer and the program responsible for determining the notification range of estimated seismic intensity. Despite the unprecedented demand, our systems handled over 900 million accesses, with data transfers exceeding 4TB, at an error rate of 0%. The Strong Motion Monitor layer received a peak access of over 23,000 requests per second.

While reinforcing our infrastructure and handling traffic incurs a cost, these expenses are offset by the support of our Supporters' Club members. We sincerely appreciate your ongoing cooperation, which allows us to maintain and improve the system's reliability.

Since last year, we have been participating as committee members of the Japan Meteorological Agency's "Study Group on the Provision of Information on Long-Lasting Tsunami." However, given the tsunami warnings issued on January 1st and April 3rd of this year, there is still more work to be done to improve the quality of the information.

As we enter the new fiscal year, many of you may be embarking on new endeavours. With the changing seasons, please take care of your health.

Ratings and Reviews

4.8 out of 5
17 Ratings

17 Ratings

hanguolaohu ,

Must-Have App for Japan Residents

This app is a must-have for residents of Japan. I like it so much that I would be willing to pay a subscription for it. It’s incredible that it’s offered for free. It has full bilingual support in Japanese and English, and the English machine translations are excellent. When the Noto Ishikawa earthquake occurred, NERV sent me a warning notification in advance with time to arrive at my geolocation with estimated intensity. Godlike capabilities. Those who don’t know this app are left in the dark.

ISeldomEverReview ,

Works nicely

It gives me very prompt notifications, oftentimes a few minutes/seconds right before my phone's features sends anything. Localized messages from Japan on my phone are translated and are hard to understand with low language skills so this app fills that gap well. Of that, I do recommend it.

Jack Pellegrini ,


Am not one to usually write app reviews but from the beautiful design to clean, in-depth features and maps, I am impressed. Shows detailed present and future severe weather events, has great earthquake realtime features, and is an overall smooth app.

App Privacy

The developer, Gehirn Inc., 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
  • Diagnostics

Privacy practices may vary, for example, based on the features you use or your age. Learn More

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