Privacy What districtry stores, what leaves your browser, and what it never collects.

Boundary street names. If you switch the map's “Boundary streets” button off or back on, the choice is kept in localStorage under districtry-boundary-streets on Illinois, New York, San Francisco, Wisconsin, Iowa, Michigan, Minnesota, Kentucky, Indiana, North Carolina, Oklahoma, South Carolina, Tennessee, Arkansas and Mississippi. It is one word, and it never leaves your browser.

The install invitation. On a phone, the map offers once to add districtry to your home screen. It records that it has asked in localStorage under districtry-install-invite, so it does not ask again. This is on Illinois, New York, San Francisco, Wisconsin, Iowa, Michigan, Minnesota, Kentucky, Indiana, North Carolina, Oklahoma, South Carolina, Tennessee, Arkansas and Mississippi. It is one word, and it never leaves your browser.

Which state you used last. Each app keeps its own two-letter tag (il, ny and so on) in localStorage under districtry-last-app on Illinois, New York, San Francisco, Wisconsin, Iowa, Michigan, Minnesota, Kentucky, Indiana, North Carolina, Oklahoma, South Carolina, Tennessee, Arkansas and Mississippi. The installed app's launcher at /app/ reads it to open that state's map. It is two letters, the next state you open replaces it, and it never leaves your browser.

Light or dark. If you use the theme toggle, the choice is kept in localStorage under districtry-theme on Illinois, New York, San Francisco, Wisconsin, Iowa, Michigan, Minnesota, Kentucky, Indiana, North Carolina, Oklahoma, South Carolina, Tennessee, Arkansas and Mississippi, so the site does not flash white on your next visit. It is one word, and it never leaves your browser. The front door reads it and never writes it, which is how the choice follows you off the map.

One display preference, per app. The school layer's type filter is remembered in sessionStorage under chi-school-type-filter on Illinois. It is a handful of true/false switches, it is erased when you close the tab, and it never leaves your browser.

A launch already counted. When you open the installed app, the launch is counted once. A mark in sessionStorage under districtry-app-launch records that, so moving between states in the same window does not count it again. This is on Illinois, New York, San Francisco, Wisconsin, Iowa, Michigan, Minnesota, Kentucky, Indiana, North Carolina, Oklahoma, South Carolina, Tennessee, Arkansas and Mississippi. It is erased when you close the app, and it never leaves your browser.

Opened in the Google Play app. If you open districtry from its Android app on Google Play, a mark in sessionStorage under districtry-play-app records that, so the pages in that window leave out the links asking for sponsorship: Google Play does not allow an app from its store to send readers to an outside payment page. The website keeps those links. This is on the front door, Illinois, New York, San Francisco, Wisconsin, Iowa, Michigan, Minnesota, Kentucky, Indiana, North Carolina, Oklahoma, South Carolina, Tennessee, Arkansas and Mississippi, and on the installed app's launcher at /app/. It is erased when you close the app, and it never leaves your browser.

A place shared into the app. When you share a place into the installed app, its launcher at /app/ leaves a mark in sessionStorage under districtry-share-in, so the map it opens can count that a share arrived. The map removes the mark as soon as it has counted it. This is on Illinois, New York, San Francisco, Wisconsin, Iowa, Michigan, Minnesota, Kentucky, Indiana, North Carolina, Oklahoma, South Carolina, Tennessee, Arkansas and Mississippi. It says nothing about the place, and it never leaves your browser.

One display preference, per app. The school layer's type filter is remembered in sessionStorage under nyc-school-type-filter on New York. It is a handful of true/false switches, it is erased when you close the tab, and it never leaves your browser.

One display preference, per app. The school layer's type filter is remembered in sessionStorage under sf-school-type-filter on San Francisco. It is a handful of true/false switches, it is erased when you close the tab, and it never leaves your browser.

A cache of each app's own files. A service worker stores the app shell when you first visit, and each layer's boundary file and officeholder roster the first time you switch that layer on (for a layer drawn from vector tiles, the pieces of its map you have looked at), so the map loads fast and those layers work offline. It holds published public data — district shapes and rosters — not anything about you.

If you install districtry, its launcher at /app/ keeps one more cache, holding only the launcher page itself, so the installed app opens with no connection.

No app here sets a cookie of its own. Google Analytics, where it runs, sets its own.

No app here asks for your location on its own. It is offered once, behind the "Use my current location" button, and your browser asks your permission before anything happens. Declining costs you nothing else on the page.

If you allow it, the coordinates your browser reports are used in the page to drop a point and answer the layer cards. The one thing that goes anywhere is a rounded pair sent to that app's GoatCounter — 2 decimal places, roughly a kilometre — which is coarse enough that it cannot pin an address and fine enough to show which part of a region the feature gets used from.

Clicking the map is the same story with no permission needed: the point is yours, and only the rounded version is counted.

Permalinks carry your point. Selecting a place writes it into the address bar as #p=41.8825,-87.6285, at full precision, along with the layers you have on. That is what makes a link shareable — and it means anyone you send the link to, and anything that logs it, gets that location. Delete the part of the URL after # to share the map without it.

Bug reports are yours to send. "Report a bug or leave a comment" prepares a draft containing what you wrote, the current page URL — which may include your point — and your browser's user-agent string. It is only ever a draft: nothing is transmitted until you submit the GitHub issue or send the email yourself, and you can edit it first. The same form sits at /feedback.html for every page that is not a map, and it fills in the address of the page you came from.

A link can open the form. A link ending in #feedback opens it, and #feedback= followed by text fills that text in, so someone can send you a form that already says what to check. That text, and a copied link to the form with what you typed, travel after the # in the address, which your browser never sends to a server or to analytics.

Places you share into the app. Once districtry is installed on an Android phone it is in the Share menu, so a place open in Google Maps can be shared straight to it. What you share arrives in the address of a request for the installed app's launcher at /app/, and the launcher's own copy on your phone answers that request. The launcher hands it to the map after the #, and the map reads it as it would a link pasted into its search box: a link that carries its position is read on your phone, a short link goes to the short-link lookup in the table above, and a place name or an address goes to the address search. When that search can't find the house at the address, the address also goes through the lookup to the Census Bureau, which the table above names too. The launcher keeps that copy from the first time the installed app opens, or from the moment you install districtry from a state's map. A share sent before then reaches this site's host, GitHub Pages, in the address of that request.

This page is versioned with the apps it describes, and it is generated from them — the build reads each app's own shipped page for the facts in the tables above, and refuses to publish a claim that has stopped being true. When the data flows change, this page changes in the same commit: the file's history is the changelog.

Questions, corrections, or a request about your data: adam@overberg.co. Because the project stores nothing about you, there is generally nothing to look up, correct, or delete on our side — but if you think that is wrong in your case, say so and it will be checked properly rather than waved away.