What the app stores on your phone
The atlas. A copy of the register billasaari.com publishes at /atlas/data/places.json is bundled into the app when the app is built, so it works with no connection; the Places tab shows which edition you have. When you are online the app refreshes it and keeps the last copy in the app’s own storage.
The places you follow. Each place you star is kept as its record id and the status you last saw for it, in the app’s own storage. That is how the app can mark a followed place whose status changed since you last looked — the comparison happens on the phone. Nothing is sent anywhere and there is no account to sync to.
The one network request
The app makes one kind of request: an HTTPS GET to billasaari.com/atlas/data/places.json to refresh the atlas, on launch and on pull-to-refresh. It carries no identifier, no location and no personal data — only the standard request headers and, when the app has one, the file’s ETag so an unchanged file is not downloaded again. billasaari.com is hosted on Vercel, whose servers see the request’s IP address in ordinary server logs; Billasaari reads no per-request data from them. No other host is ever contacted by the app.
Location
The Nearby tab can sort the atlas by distance from where you are. It asks Android for foreground location permission only when you tap Use my location, never at launch and never in the background. The position is read once, kept in that screen’s memory while it is open, used on the phone to sort the list, and then dropped. It is never written to storage, never attached to the atlas request and never sent to Billasaari or anyone else. If you decline, the tab says so and offers the region filter instead. You can withdraw the permission at any time in Android Settings › Apps › Billasaari › Permissions.
What the app does not do
- No account, sign-in or registration.
- No analytics or crash-reporting SDK, no advertising, no advertising identifier.
- No notifications and no background work: the “changed” marker is worked out when you open the app.
- No payments, in-app purchases, wallet or prices: the app has no financial features.
- No WebView: links open in your browser. Links to Billasaari’s and the studio’s own websites carry plain UTM tags, so billasaari.com — which measures its own visits with Google Analytics — can tell app visits from web visits; links to operators’ pages and other sources open untouched.
Deleting your data
Everything the app holds is on your phone. Uninstalling the app, or clearing its storage in Android Settings, erases the atlas copy and the places you follow. There is nothing to delete on our side.
The data in the atlas
The atlas describes places and the organisations behind them, not people. It is published under Creative Commons Attribution 4.0 International with the attribution “Billasaari Bitcoin Places Register (billasaari.com/atlas), CC BY 4.0”. Corrections: support.
Who publishes the app
Published by Billasaari (billasaari.com), Helsinki, Finland. Questions about this page: hello@jukkablomberg.com.
Updated 2026-10-02. Google Play: Billasaari: Bitcoin Places (package com.billasaari.app).