Last updated: 26 July 2026
HEA : High Entropy Alloys is an offline high-entropy-alloy design and phase-prediction tool. It computes configurational entropy, enthalpy of mixing, atomic-size difference, valence-electron concentration and the other classic design parameters from published correlations, entirely on your device. It has no account, no server, and no way to reach the internet. This policy explains, plainly, what that means.
HEA stores exactly two things: whether you prefer atomic percent or molar ratio for composition, and whether you prefer kelvin or Celsius for temperature. Those two display preferences live in the app's private storage on your device so the app remembers them next time you open it. Nothing else is written anywhere.
The formula you type into the calculator and the alloys you look up in the literature evidence set are held in memory only while you are using the screen. They are not saved to disk, not kept in a history, and not sent anywhere. Close the app and they are gone.
Most apps that promise privacy still ship with the ability to reach the internet and simply choose not to use it. HEA does not have that ability. The release build declares no INTERNET permission, which means Android itself will refuse any network request the app might make. You can verify this on the app's Play Store listing, where the permissions section will show none, or with any APK inspection tool.
The element property table, the binary mixing-enthalpy matrix, the literature evidence set, all equations, and all citations are bundled inside the app. Nothing is fetched, and there is nothing to fetch.
HEA does not collect names, email addresses, contacts, location, photos, device identifiers, usage analytics, crash reports, or any other personal information. It does not know which alloys you looked at, what formula you entered, or that you opened it at all. There is no mechanism by which it could report any of this.
HEA requests no runtime permissions. It does not ask for camera, photos, storage, microphone, location, contacts, or notifications. The only entry in its manifest is an Android system permission that the app defines for itself, which grants no access to your device or your data and is added automatically by the Android support libraries.
HEA gives estimates from published empirical correlations, and the phase rules it applies are screening rules rather than a phase diagram. It is not a certification tool and does not issue specifications. The correlations carry scatter, they were fitted on particular alloy families, and a rule that passes is not a guarantee that a single-phase solid solution will form. Every parameter in the app shows its equation, its source, and the limits of that source, and a parameter is withheld outright when the bundled data cannot support it. Confirm any candidate alloy experimentally before relying on it.
The literature evidence set is derived from a published open dataset (Chizhevskiy et al., High Entropy Alloys Database generated with Large Language Model, Scientific Data 13:612, 2026; data at Mendeley 10.17632/j75v9bbbjz), used under the Creative Commons Attribution 4.0 licence and attributed in the app's About screen. It was extracted from published papers by a language model rather than curated by hand, so the app states its accuracy caveat wherever it is shown and links each record to its source DOI. It contains no personal data. Including it involves no data collection from you and no network access.
HEA does not knowingly collect any data from anyone, including children. There is nothing to collect.
If this policy ever changes, the updated version will be posted at this same address with a new date above. Any change that would affect data handling would be described here before it took effect.
Questions about this policy can be sent to contact@futigo.io.