Comparison

NERV Disaster Prevention vs Moondot

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

NERV Disaster Prevention

This app provides critical disaster warnings for earthquakes, tsunamis, volcanic eruptions, and weather-related events like floods and landslides. It offers real-time information optimized for your current and registered locations, helping you make informed decisions during emergencies.

Highlights
  • Earthquake, tsunami, volcanic eruption warnings
  • Weather-related disaster prevention info
  • Location-optimized alerts
  • Real-time map interaction
  • Urgency-based notification sorting
  • Critical Alerts for imminent danger
  • Barrier-free design
Features
Currently charting
Read full description

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. https://nerv.app/en/supporters.html [Privacy] 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. https://nerv.app/en/support.html#privacy

About

Moondot

This app offers a customizable, retro-style pixel art tracker for moon phases. It provides offline functionality with home and lock screen widgets, allowing users to view lunar statistics and travel through time to see past or future phases.

Highlights
  • Customizable pixel art moon
  • Home Screen widgets
  • Lock Screen widgets
  • Offline functionality
  • Time travel feature
  • Lunar statistics
Features
Read full description

Track the moon in retro style. Moondot is a customizable pixel-art moon phase tracker that renders the lunar cycle with clean, minimalist visuals. CUSTOMIZABLE & WIDGET-READY  Make the moon your own. Moondot features customizable Home Screen widgets that let you keep the current phase in view at all times. Choose between a data-rich layout or a simple, stunning moon. You can adjust the color, pixel grid resolution, and add lunar surface detail to your view. See moon phase information at a glance with Lock Screen widgets. MATH-BASED & PRIVATE  Moondot models the moon using standard astronomical algorithms right on your device. Because it runs on pure math, it works completely offline. There is no internet connection, no tracking, and absolutely no data collection. Just you and the moon. Location is used only to provide moon position, moonrise, and moonset estimates for your area. FEATURES  • Custom Control: Adjust the color and “retro resolution” of the pixel art moon to match your personal aesthetic. • Home Screen Widgets: Beautiful, customizable widgets in Small and Medium sizes. • Lock Screen Widgets: Get glanceable moon phase information right on the Lock Screen. • Time Travel: Drag the moon to spin through time and check the phase for dates in the past or future.  • Lunar Stats: View illumination percentages, moon position, estimated moonrise & moonset times, and the date of the next Full Moon. • 100% Offline: No ads, no tracking, and no internet required.  NO ADS, NO SUBSCRIPTIONS  Moondot is a one-time purchase.

Screenshots

NERV Disaster Prevention4 screens
Moondot4 screens

Verdict

The call

The clearest difference is price: NERV Disaster Prevention at Free against Moondot's $2.99. NERV Disaster Prevention also leads on chart position (#60 vs unranked) and iOS requirement (15.1 vs 18.6). Moondot's advantage is in-app purchases (none vs 2) and review sentiment (100% vs 80%). On update cadence, ads and device support there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

NERV Disaster Prevention is free to download; Moondot costs $2.99 up front. NERV Disaster Prevention sells 2 in-app purchases, starting at $2.49 per month. Moondot asks for nothing beyond the download.

UpkeepUpdate frequency

NERV Disaster Prevention ships an update every 6 weeks, Moondot every 5 weeks. The most recent releases landed on November 11, 2026 and November 9, 2026 respectively.

Scorecard6 real differences · 5 level
NERV Disaster Prevention versus Moondot: the parameters behind the verdict, then further details
ParameterNERV Disaster PreventionMoondot
PriceFree — better$2.99
Rating4.7 (48 ratings) — better—
Positive reviews80.5% of reviews100.0% of reviews — better
Number of ratings48 — better—
Update frequencyEvery 6 weeksEvery 5 weeks — better
AdsNoNo
In-app purchasesYesNo — better
MonetizationFree with in-app purchases — betterPaid
Best chart rank#60 — better—
DevicesiPhone, iPod — betteriPhone
Requires iOS15.1 — better18.6
Further details — not scored
Size76 MB9 MB
Age rating4+4+
DeveloperGehirn Inc.James Buell Jr

Customer experience

NERV Disaster Prevention

All ratings47 ratings
Positive91.5%
Neutral2.1%
Negative6.4%
Written reviews82 reviews
Positive80.5%
Neutral4.9%
Negative14.6%

Moondot

Written reviews1 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

In-app purchases

2 purchases

NERV Disaster Prevention

Subscriptions2
  • E Plan$2.491 Month
  • EE Plan$4.491 Month
None

Moondot

No in-app purchases

Questions

Is NERV Disaster Prevention free?
NERV Disaster Prevention is free to download, with in-app purchases available.
Is Moondot free?
Moondot costs $2.99, with no in-app purchases.
Do NERV Disaster Prevention or Moondot have ads?
Neither NERV Disaster Prevention nor Moondot shows ads.
Which is updated more often, NERV Disaster Prevention or Moondot?
NERV Disaster Prevention ships an update every 6 weeks, and Moondot every 5 weeks. Most recently, NERV Disaster Prevention was updated on November 11, 2026 and Moondot on November 9, 2026.

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