Back to Flea Market & Price Search

Privacy Policy

Last updated: June 2026

Flea Market & Price Search (フリマ・通販 一括検索; the "App") is designed with your privacy in mind. It requires no account and collects no directly-identifying personal data. To find and fix problems and improve the App, it collects anonymous crash/diagnostic data via Firebase Crashlytics; see "Crash and Diagnostic Reporting" below.

In short. Your searches stay on your device. The App shows each marketplace's own live page in an in-app browser — it never scrapes or re-hosts listings — and shares nothing about your activity with us or with advertisers.

Information We Collect

The App collects anonymous crash/diagnostic data (Firebase Crashlytics) — see the section below. It does not:

  • Require an account or login.
  • Collect personal information (PII) such as your name, email, phone number, or address.
  • Bundle any third-party advertising SDKs, or sell your data.
  • Access your location, contacts, photos, camera, or microphone.

How the App Works

Searching across marketplaces

You compose a search once (keyword, price range, sale status, sort) and the App shows each marketplace's live official results page in an in-app browser tab (and can hand off to the marketplace's official app). Supported marketplaces span flea-market, auction and EC/online-shopping services (Mercari, Rakuma, Yahoo Auctions, Yahoo!フリマ, Amazon, Rakuten, Yahoo Shopping, Kakaku, …); which sites appear, and their order, is your choice in Settings. Your search definitions are stored only on your device and are never sent to any server of ours.

The in-app browser loads each marketplace's page directly on your device, the same way any web browser does. Those sites are operated by third parties and have their own privacy policies and cookies, which apply while you view their pages. The App does not read, store, scrape, or transmit the content of those pages, and we operate no servers that receive it.

New-listing alerts (optional)

Only for saved searches you explicitly turn alerts on for, the App fetches that marketplace's results page in the background on your device and diffs it against previously stored listing identifiers (a hash of the URL path).

  • The fetched HTML is parsed solely to compute identifiers, then discarded immediately.
  • Titles, prices, images, and descriptions are never stored or transmitted.
  • The only thing kept is the identifier (hash) that uniquely represents a listing — this is not personal information.
  • Nothing ever leaves your device. We operate no servers and share no data with any third party.
  • Notifications contain a count only (e.g. "New listings: N for 'keyword'") and include no item content.

In other words, the same data-minimizing model — fetch → diff → discard, identifiers only — applies whether or not you use alerts. No marketplace content, search data, or listing data is ever transmitted off your device or collected by us.

Crash and Diagnostic Reporting

The App uses Firebase Crashlytics (a service provided by Google) to detect and fix crashes and stability problems. When the App crashes or hits a serious error, Crashlytics sends an anonymous report to Google on our behalf. These reports may include:

  • The crash stack trace and the type of error.
  • Diagnostic device/OS information — device model, operating-system version, app version, language/region, and the app's state at the time of the crash.
  • A randomly generated, app-specific installation identifier used to group a device's crashes together. It is not the advertising identifier (IDFA/AAID) and is not used to track you across other apps or websites.

This crash and diagnostic data:

  • Contains no account, name, email, location, or contact information, and none of your search keywords, search history, or listing data.
  • Is used only to keep the App stable — never for advertising, profiling, or cross-app/website tracking. No App Tracking Transparency prompt is shown.
  • Is processed by Google as our data processor under Google's terms. See Google's privacy information at firebase.google.com/support/privacy.

Where Data Is Stored

Your saved searches, search history, and (when alerts are used) listing identifiers are all stored in a secure local database on your device. Uninstalling the App removes them from your device.

Sharing With Third Parties

We do not sell or share your data for advertising or marketing. The only third party that receives any data is Google, which processes the anonymous crash and diagnostic reports described above on our behalf (via Firebase Crashlytics). We share no other data with anyone.

Relationship With Marketplaces

The App is not affiliated with or endorsed by any marketplace. All service names and trademarks belong to their respective owners. Search results are shown by loading each marketplace's own live official page in an in-app browser; the App never scrapes, re-renders, or re-hosts their content.

Children's Privacy

Because the App collects no personal data — only anonymous crash and diagnostic data — all users, regardless of age, are treated identically.

Changes to This Policy

If we update this policy, we will revise the "Last updated" date on this page.

Contact

For questions about this policy, please contact ndlab.contact@ndlab.jp.