Privacy Policy

What Entropy stores, and where

To shuffle your music, Entropy reads the music library that is already on your iPhone and keeps its own index of it: song, artist, album, genre and playlist names, along with play counts, skip counts and last-played dates.

That index lives in a database inside Entropy's own app container on your device. It is not copied to a server, because there is no server. It is not synced to iCloud. Deleting the app deletes it.

Why Entropy asks for music library access

iOS asks your permission before Entropy can see your library. Entropy uses that permission for exactly two things:

• reading your songs and playlists, so it has something to shuffle; and
• reading Music's existing play counts, skip counts and ratings once, so the shuffle algorithms start with real listening history rather than a blank slate.

Entropy itself only ever reads your library; it does not write to it. Playback runs through Apple's own music player, and that player counts a play in Music the same way it would if you had pressed play in the Music app — so listening in Entropy still counts where you would expect it to. Playlists are never copied: they are read fresh from Music each time the app launches.

If you decline the permission, Entropy has nothing to shuffle and will say so. You can change your mind at any time in Settings › Privacy & Security › Media & Apple Music.

What Entropy does not do

• No analytics or tracking. There is no analytics SDK in the app — no Firebase, no Sentry, no Mixpanel, nothing of that kind. No usage data, crash-reporting of our own, device identifiers or advertising identifiers are gathered.
• No network requests, except the one you ask for. The only time the app goes online is to download Entropy FM's voices, and only after you press the button to do it (see below). It does not phone home, check for messages, or fetch anything else.
• No accounts. There is nothing to sign up for and no password to forget.
• No advertising, and no sale or sharing of data. Nothing is collected, so there is nothing to sell, share, or hand to a data broker.
• No third-party SDKs that collect data. Apart from Apple's own frameworks and its own code, Entropy includes one open-source library, which runs the voice models on your phone. It collects nothing and reports to no one.

Entropy FM

Entropy FM's between-song segments are assembled on your device. The human host's lines are audio recordings bundled inside the app. The digital host, Alex, speaks in whichever voice you choose: one of Entropy's own, or one of the voices built into iOS. Either way the speech is generated on your phone. Nothing you listen to is transmitted for processing, and nothing is broadcast — Entropy FM is a station with exactly one listener.

Entropy's own voices come from an open-source speech model that runs on your phone. The model is about 110 MB, so it is not included in the app. Entropy offers to download it, says how big it is, and fetches nothing until you press the button. It comes from models.entropy.fm, which is run by Entropy on Cloudflare. The download asks for the model files and nothing else: no account, no identifier, and nothing from your library. Like any download, the request reaches Cloudflare with your IP address, the app's name and build number, and which version of iOS it is running on, which Cloudflare handles as described under This website. After that the voices work offline, and you can remove them from the voice list in Entropy FM's settings.

Siri, Shortcuts and widgets

Entropy's Siri phrases, Shortcuts actions and home-screen widgets are handled by iOS. Apple's own privacy policy governs how Siri processes what you say to it; Entropy receives only the resulting instruction, such as which mode to start.

What Apple sees

Downloading Entropy is a transaction between you and Apple, and Apple gives developers aggregate App Store statistics — how many downloads, in which countries, that sort of thing. If you have turned on iOS's “Share With App Developers” analytics setting, Apple may also pass along anonymised crash and usage reports. All of that comes from Apple, not from anything Entropy does, and none of it identifies you. You can turn it off in Settings › Privacy & Security › Analytics & Improvements.

This website

entropy.fm, and the voice downloads at models.entropy.fm, are hosted on Cloudflare. The site sets no cookies and loads no third-party scripts or fonts. Cloudflare processes requests to serve the site and the downloads, and keeps standard, short-lived server logs — including IP addresses — for security and abuse prevention, as described in Cloudflare's privacy policy.

Entropy uses Cloudflare's built-in analytics to see how much the site and the downloads are used: aggregate counts such as visits, pages viewed, bandwidth, and which countries and browsers requests come from. They are worked out from the requests Cloudflare already handles. There is no tracking script on the page and no cookie, and they are never used to identify or follow an individual visitor.

Email

If you write to support@entropy.fm, that message and your email address are kept only so the conversation can be answered and any bug you reported can be chased down. They are not added to a mailing list or used for anything else.

Children

Entropy is not directed at children and collects no personal information from anyone, of any age.

Your rights

Regulations such as the GDPR and the CCPA give you rights to access, correct, export or delete the personal data a company holds about you. Entropy holds none, so there is nothing to request. The data the app keeps on your own device is already yours: you can erase all of it by deleting the app.

Changes

If this policy ever changes, the revised version will be posted here with a new date at the top. Should a future version of the app ever begin collecting anything, that change will be described here before it ships.

Contact

Questions about any of this are welcome at support@entropy.fm.