# Open Data Catalog Japan — Explore datasets and live APIs

> Explore datasets and live APIs (iPhone/iPad app by Naoki Chiba.)

- Source: https://appshunter.io/ios/app/open-data-catalog-japan/id6791758964 (this page in markdown: same URL + `.md`)
- Developer: [Naoki Chiba](https://appshunter.io/developer/1895372512)
- Category: Reference, Utilities
- Price: Free
- Age rating: 4+
- Requires: iOS 17.0 · 6 MB
- Languages: American English, Japanese
- Released: 2026-07-20
- Data updated: 2026-10-31

## What is Open Data Catalog Japan?

Explore open data from Japanese national and local government portals in one app.

FEATURES
- Search catalogs across registered sources and filter by theme, format, organization and update information.
- Browse dataset details, resources, licenses and source links.
- Preview CSV, TSV, JSON, GeoJSON, images and PDFs, including supported files in ZIP archives.
- View supported Shapefile maps and attribute tables.
- Search supported data tables, or search within loaded previews.
- Keep a local notebook of favorites, notes and tags.
- Add custom CKAN-compatible portals.
- Download the Tokyo API Catalog and call its public APIs.
- Choose Japanese or English in Settings.

PLEASE NOTE
Dataset titles, descriptions, field names, search terms and original source documents retain their source language. Coverage and availability depend on each portal. Some previews have file-size, row or coordinate limits. Searches are sent to the selected portals; notebook searches stay on your device. This app is independent and is not an official app of the portals. Check each dataset license before using or sharing data.

## Is Open Data Catalog Japan safe?

Not enough ratings yet to assess Open Data Catalog Japan.

## Is Open Data Catalog Japan legit?

Open Data Catalog Japan appears legitimate, with a few gaps. The AppsHunter Legitimacy Score for Open Data Catalog Japan is 65 out of 100 points across 7 verification signals from App Store and developer data.


## Version history (last 5 releases)

### 1.4.1 — 2026-10-25

• Now supports iPhone Duo. Dataset lists and CSV table previews use the full unfolded screen.

### 1.4 — 2026-10-03

Added English throughout search, previews, notebook, settings and app error messages. Choose Japanese or English in Settings. Fixed an issue where the other-apps list closed immediately after opening.

### 1.3.1 — 2026-09-30

アプリアイコンを新しくしました。

### 1.3 — 2026-08-15

・東京都が公開する呼び出し可能なライブAPI（約71,000件、キー不要）を新しいデータソース「東京都APIカタログ」として追加しました
・設定から取り込むと横断検索にも加わり、検索結果の詳細画面から実際にAPIを呼び出してJSON形式の結果を確認できます

### 1.2 — 2026-07-26

・ZIP内のCSV／TSV／JSON／GeoJSON／PDF／画像を選んで表示できるようになりました
・GeoJSONとShapefileの地図表示、Shapefile属性表の検索・並べ替えに対応しました
・利用条件や説明ページを経由してダウンロードするデータを、アプリ内プレビューへ受け渡せるようになりました
・対応データセットの中身検索と、ネタ帳の端末内検索を追加しました
・検索結果の一致理由や0件時の条件切り替えなど、検索の使い勝手を改善しました

## More apps by Naoki Chiba

- [Bus Location MAP: Tokyo](https://appshunter.io/ios/app/bus-location-map-tokyo/id6763555056)
- [Prime Logic](https://appshunter.io/ios/app/prime-logic/id6766418614)
- [Giken Band Ensemble](https://appshunter.io/ios/app/giken-band-ensemble/id6768064223)
- [Haneda Approach 3D](https://appshunter.io/ios/app/haneda-approach-3d/id6779796875)
- [Airport Weather Japan](https://appshunter.io/ios/app/airport-weather-japan/id6779813293)
- [Compose Studio Viewer](https://appshunter.io/ios/app/compose-studio-viewer/id6780131972)

All apps by Naoki Chiba: https://appshunter.io/developer/1895372512

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-10-31.*