# 海天気.jp vs Tide & Sky

The clearest difference is in-app purchases: 海天気.jp at none against Tide & Sky's 2. 海天気.jp also leads on iOS requirement (15.6 vs 18.0). Tide & Sky's advantage is update cadence (every 2 days vs every 4 months). On price, ads and device support there is nothing between them.

Both are free to download. Tide & Sky sells 2 in-app purchases, starting at $1.99 per month. 海天気.jp asks for nothing beyond the download.

海天気.jp ships an update every 4 months, Tide & Sky every 2 days. The most recent releases landed on October 19, 2026 and October 5, 2026 respectively.

## The numbers

| Metric | 海天気.jp | Tide & Sky |
| --- | --- | --- |
| Price | Free | Free |
| Positive reviews | 85.0% of reviews | — |
| In-app purchases | **No** | Yes |
| Ads | Yes | Yes |
| Update frequency | Every 4 months | **Every 2 days** |
| Monetization | Ad-supported | — |
| Size | 37 MB | 27 MB |
| Requires iOS | **15.6** | 18.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, Apple Watch |
| Age rating | 4+ | 4+ |
| Developer | [Risesystem, inc.](https://appshunter.io/developer/427437064) | [AO Inc.](https://appshunter.io/developer/762383198) |

## 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


### Tide & Sky

[App page](https://appshunter.io/ios/app/tide-and-sky/id6809079481)

**Features:** Apple Watch app

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Tide & Sky Premium Monthly | $1.99 | per month |
| Tide & Sky Premium Yearly | $14.99 | per year |


## Frequently asked questions

### Is 海天気.jp free?

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

### Is Tide & Sky free?

Tide & Sky is free to download, with in-app purchases available.

### Do 海天気.jp or Tide & Sky have ads?

Both 海天気.jp and Tide & Sky show ads.

### Which is updated more often, 海天気.jp or Tide & Sky?

海天気.jp ships an update every 4 months, and Tide & Sky every 2 days. Most recently, 海天気.jp was updated on October 19, 2026 and Tide & Sky on October 5, 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.*