# 海天気.jp vs Digital AMeDAS

The clearest difference is review sentiment: 海天気.jp at 85% against Digital AMeDAS's 31%. Digital AMeDAS's advantage is ads (none vs shown) and update cadence (every 10 days vs every 4 months). On price, in-app purchases, device support and iOS requirement there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

海天気.jp ships an update every 4 months, Digital AMeDAS every 10 days. The most recent releases landed on September 10, 2026 and September 18, 2026 respectively.

## The numbers

| Metric | 海天気.jp | Digital AMeDAS |
| --- | --- | --- |
| Price | Free | Free |
| Positive reviews | **85.0% of reviews** | 30.8% of reviews |
| In-app purchases | No | No |
| Ads | Yes | **No** |
| Update frequency | Every 4 months | **Every 10 days** |
| Monetization | Ad-supported | **Free** |
| Size | 37 MB | 46 MB |
| Requires iOS | **13.0** | 14.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Risesystem, inc.](https://appshunter.io/developer/427437064) | [気象工学研究所](https://appshunter.io/developer/1635872250) |

## What reviewers say

### 海天気.jp

[App page](https://appshunter.io/ios/app/jp/id1641843175)

Get detailed, hourly weather forecasts for over 8,000 marine spots, including wind, temperature, and wave height. Visualize precipitation with clear icons and access 14-day outlooks for planning. Also provides city-level forecasts and rain cloud movement.

**Highlights:** Hourly forecasts for 8,000+ marine spots, Up to 84-hour pinpoint weather predictions, 14-day weather outlooks, Rain cloud and lightning movement visualization, Tide graphs and sea temperature maps, City-level weather forecasts, Favorite spot bookmarking

**In-app purchases:** none


### Digital AMeDAS

[App page](https://appshunter.io/ios/app/digital-amedas/id6479399767)

Access and analyze meteorological data from a network of automated weather stations. This application helps users obtain detailed weather information for specific locations, aiding the Japan Meteorological Agency in understanding data utilization and improving services.

**Highlights:** Access AMeDAS meteorological data, View spatially analyzed data, Obtain data for specific locations, User attribute registration, Feedback and request submission

**Features:** Vision Pro support

**In-app purchases:** none


## Frequently asked questions

### Is 海天気.jp free?

海天気.jp is free to download, with no in-app purchases.

### Is Digital AMeDAS free?

Digital AMeDAS is free to download, with no in-app purchases.

### Do 海天気.jp or Digital AMeDAS have ads?

海天気.jp shows ads; Digital AMeDAS does not.

### Which is updated more often, 海天気.jp or Digital AMeDAS?

海天気.jp ships an update every 4 months, and Digital AMeDAS every 10 days. Most recently, 海天気.jp was updated on September 10, 2026 and Digital AMeDAS on September 18, 2026.

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*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*