Privacy Policy

Last updated: September 29, 2026 · 中文版 ↓

This policy explains how the EH Lab app for iPhone and iPad (listed on the App Store as “Extended Horizon Lab”) and the EH Lab web app at extendedhorizon.com/app (together, “the app”) handle your information. Everything below applies to both, except where the section “On the web” says otherwise. The app is made for the members of the Extended Horizon Lab (“the lab”, “we”) in the Department of Computer Science at North Carolina State University, directed by Prof. Qiao (Georgie) Jin.

In short

• The app is for lab members. It has no ads, no tracking and no analytics, and we never sell your information.
• We use your Google name and email address to check that you are on the lab’s member list.
• When you borrow a device, your name and the dates go on the lab’s equipment sheet, where other members can see them.
• Your questions in EH LLM, the tab for searching the lab’s documents, go to the lab’s own server and on to OpenAI (the iPhone and iPad app asks your permission first).
• If you choose to show your own meetings with the advisor, the app reads your calendar on your device only. Those events are never sent to the lab or anyone else.

What the app handles and where it goes

Signing in with Google

• You sign in on Google’s own sign-in page. With your permission, Google gives the app your name, email address, Google account ID and basic profile, and permission to see events on public calendars.
• To check that you are on the lab’s member list, the app sends a Google sign-in token, which contains your name, email address and Google account ID, to the lab’s archive server. If you are on the list, the server issues a session for the app and keeps a record of it. TODO — confirm with the server’s code before publishing: “The server stores the session token only in hashed form.” Delete this sentence if it is not true.
• Each time you view or change the equipment list, the app sends your Google sign-in token to the lab’s equipment service (a Google Apps Script run by the lab). The service asks Google to confirm the token and checks your email address against the member list.
• On your device, the app keeps your Google tokens and your lab session in the iOS Keychain.

The lab calendar

• The lab calendar is a public Google Calendar. The app reads it from Google with the permission to see events on public calendars, and keeps a copy on your device so the schedule still shows when you are offline.

Your own calendar (optional, off unless you turn it on)

• Only if you turn on Show my meetings with the advisor in Settings does the app ask Google for read-only access to your calendars. It then reads your primary calendar for meetings that include the lab’s advisor.
• Those meetings are read directly from Google by the app on your device, shown only in the app on that device, and kept only in the app’s memory while it runs. They are not saved to storage and are never sent to the lab’s servers, to OpenAI or to anyone else.
• Turning the setting off stops the reading at once.

Equipment

• When you borrow a device, the app writes the borrower’s name, the time it was borrowed and the due date into that device’s row on the lab’s equipment sheet, a Google Sheet kept by the lab. When the device is returned, those cells are cleared.
• Lab members, and anyone else the lab shares the sheet with, can see who has which device. Earlier values can remain in the sheet’s version history, which the sheet’s editors can see.
• A lab member can record a loan for another member; that member’s name is then written instead.

EH LLM: searching and asking about lab documents

• When you use the EH LLM tab, your question is sent, with your session, to the lab’s archive server, which the lab runs on Amazon Web Services (AWS) in the United States.
• Find files: the server sends your question to OpenAI to reword it for the search.
• Ask: the server sends your question and the matching passages from the lab’s archive to OpenAI, which writes the answer.
• The iPhone and iPad app asks for your permission before any question is sent to OpenAI; if you do not agree, nothing is sent. The web app does not ask: a note under the question box says what is sent to OpenAI, and nothing is sent until you press Find files or Ask.
• The lab’s archive server: TODO — confirm and replace this sentence, for example “does not keep your questions after answering them” or “keeps request logs, including questions, for N days to fix problems, and then deletes them.”
• OpenAI processes this information to provide its service to the lab, under OpenAI’s API terms and privacy policy. At the time of writing, OpenAI states that information sent through its API is not used to train its models unless the customer chooses to allow it, and may be kept for up to 30 days to detect abuse, or longer where the law requires. See OpenAI’s policies.
• Your recent questions and answers (up to 50) are saved on your device so you can look at them again. They are excluded from device backups, deleted when you sign out, and can be cleared at any time in EH LLM → History.

Settings on your device

• The app keeps your choice of language, answer language and calendar sharing on your device.

On the web (extendedhorizon.com/app)

The web app does the same things as the iPhone and iPad app, with these differences:

• Where it is kept: the web app keeps your sign-in tokens, the lab session, the equipment session, the lab member list, a copy of the lab calendar, your recent EH LLM questions (up to 50) and your settings in your browser’s local storage for extendedhorizon.com, not in the iOS Keychain. Signing out removes them. On a shared or public computer, always sign out when you finish.
• Signing in: Google gives the web app your name, email address, Google account ID and basic profile. It does not ask for calendar access at sign-in.
• Equipment: at sign-in the web app sends your Google sign-in token to the lab’s equipment service once. The service checks it with Google and your address against the member list, then gives the web app its own session, which lasts up to 30 days, together with the lab’s member list (names, email addresses and whether a headshot exists) so the app can show who has which device. Later requests use that session, and your membership is checked again each time.
• Lab calendar: the web app reads the public lab calendar from Google with the lab’s own API key, so it needs no calendar permission from your account.
• Your own calendar: if you turn on Show my meetings with the advisor, Google gives the web app read-only access that lasts about an hour. When it has run out, the web app may briefly visit Google’s page to renew it when it starts. The meetings are still kept only in memory and never sent anywhere.
• Hosting: the web app’s files are served by GitHub Pages, which, like any web host, receives your IP address and browser information when your browser downloads them. The web app loads no third-party scripts, ads or trackers.

What we don’t do

• No advertising, no tracking across other companies’ apps or websites, no analytics or crash-reporting services, and no selling or renting of your information.
• The app does not access your location, contacts, photos, camera, microphone or health data.
• The lab does not use your information to train AI models.

Who can see your information

• Other lab members: your name on devices you have borrowed.
• Lab managers who look after the member list, the archive server and the equipment service: the member list, session records and server logs.
• Service providers that handle information for the lab: Google (sign-in, Google Calendar, the equipment sheet and the Apps Script service), Amazon Web Services (hosts the archive server), OpenAI (EH LLM questions) and GitHub (serves the web app’s files). Each handles information under its own terms and privacy policy, and may process it outside the United States.
• Others, only when required by law or by North Carolina State University policy.

How long information is kept

• On your device: until you sign out, clear the EH LLM history or delete the app. Sign out before deleting the app, so that its sign-in tokens are also removed from the iOS Keychain. On the web, until you sign out or clear the site’s data in your browser.
• Lab member list: while you are a member of the lab. A lab manager removes you when you leave.
• Archive server: TODO — confirm how long session records and server logs are kept, for example “sessions end when you sign out or after N days without use; logs are deleted after N days.”
• Equipment sheet: loan details until the device is returned; earlier values may remain in the sheet’s version history.
• Google, Amazon Web Services and OpenAI: according to their own policies. The lab does not control how long they keep information.

Your choices

• Stop reading your calendar: turn off Show my meetings with the advisor in Settings.
• Keep your questions away from OpenAI: in the iPhone and iPad app, do not give the permission; on the web, do not press Find files or Ask; or do not use the EH LLM tab.
• Clear EH LLM history: EH LLM → History → Clear history.
• Sign out: Settings → Sign out.
• Remove the app’s access to your Google account: go to Google Account → Third-party connections. This signs the app out of Google on all of your devices; you will need to sign in again to use it.
• Leave the member list, or ask what the lab holds about you and have it deleted: contact us below. Loans of devices you still have stay on the sheet until the devices are returned.

Children

The app is for members of a university research lab and is not directed to children under 13. We do not knowingly collect personal information from children under 13. If you believe we have, contact us and we will delete it.

Security

All connections use HTTPS. Sign-in tokens are kept in the iOS Keychain, or on the web in the browser’s local storage for extendedhorizon.com. TODO — keep “and the archive server stores session tokens only in hashed form” only if the server really does. Only people on the lab’s member list can use the archive server and the equipment service. No system is completely secure, but we take reasonable steps to protect your information.

Google API Services

The app’s use and transfer of information received from Google APIs adheres to the Google API Services User Data Policy, including the Limited Use requirements.

Changes to this policy

If we change this policy, we will update this page and the date at the top, and tell lab members about significant changes.

Contact

Prof. Qiao (Georgie) Jin
Extended Horizon Lab
Department of Computer Science, North Carolina State University
1730 Varsity Dr, Raleigh, NC 27606, USA
Email: qjin4@ncsu.edu