Article 1 (Purpose)
The developer of Touchstone (the "Developer") adopts this Privacy Policy to protect the personal information of people who use the Touchstone iPhone app, Mac app and Chrome and Safari extensions (the "Service"), and to handle their privacy concerns promptly, in line with applicable law including Korea's Personal Information Protection Act.
Article 2 (Principles)
- The Developer runs no server and does not collect or store your personal information when you use the Service.
- The Service requires no sign-up and no login to the Developer, and uses no ads and no analytics.
- Your information is processed on your own devices, and is sent only to the outside services you choose yourself (Article 6).
Article 3 (Publication)
The address of this policy is published on the Touchstone website and on the store pages of the Service, so you can read it at any time.
Article 4 (Changes)
- This policy may be revised when laws or guidelines change or when the Service changes.
- Changes are announced on the website at least 7 days before they take effect, and at least 30 days before for changes that significantly affect your rights.
Article 5 (Information collected)
The Developer does not collect your personal information. In particular, the Developer does not receive or store:
- Member details such as name, email address or phone number
- Usage records, access records or device identifiers
- The text of the web pages you check and its verdicts, your API keys, or the pairing secret
- Payment details: the Service is free, and the Developer receives no payment details.
Article 6 (What leaves your devices)
The Service sends the following only on sites where you press "Check" or have turned on auto-check. It goes directly to the service you chose; the Developer never receives it. Each of those services handles it under its own privacy policy.
| Data | Sent to | Why |
|---|---|---|
| Text of the web page being checked | The AI you choose: OpenAI (when signed in with your ChatGPT plan, through the Mac app), Anthropic, OpenAI or Google (your own API key), or a local server on your computer | To pick out claims and judge whether they are true |
| Key words of each claim | Wikipedia search (when you chose Wikipedia as the search option) | To find evidence |
| Paper DOIs in claims | Crossref | To check that cited papers exist |
Article 7 (What stays between your own devices)
- Touches on the iPhone and haptic signals go only between your iPhone and your Mac, over the same Wi-Fi, a network created by a cable, or a direct device-to-device link. The link is authenticated with the secret shared by the QR code on your Mac's screen and is encrypted.
- The verdict for the sentence under the cursor (correct, uncertain, wrong) goes from the Mac app to the iPhone through the Mac app. The sentence itself is not sent.
Article 8 (What is stored on your devices, and for how long)
The following is stored only on your devices and is never sent to the Developer. It is kept until you delete the app or the extension, or delete the item yourself.
- Pairing secret and ChatGPT sign-in tokens: the device keychain (not synced to other devices)
- API keys, settings and cached verdicts: the browser extension's storage
- Trackpad and haptic settings, and the address of the Mac to connect to: app settings
Article 9 (Permissions the Service asks for)
- Camera (iPhone): only to scan the pairing QR code on your Mac's screen. No photos or videos are saved or sent.
- Local network (iPhone, Mac): to connect your own devices on the same network.
- Accessibility (Mac): to move the Mac's cursor and click from the iPhone.
Article 10 (Deletion)
- Deleting the apps and the extension deletes the app settings and the extension's storage.
- Keychain items may remain after an app is deleted, depending on the device's rules. Signing out of ChatGPT in the Mac app revokes its sign-in tokens, and "Make a new QR code" makes the previous pairing secret unusable. On a Mac you can also delete these items yourself in the Keychain Access app.
Article 11 (Third parties and outsourcing)
The Developer does not provide your personal information to third parties and does not outsource its processing. The transfers in Article 6 go from your device directly to the service you selected.
Article 12 (Website, cookies and access logs)
The website uses no cookies, no analytics, and no external fonts or scripts. It is delivered by a hosting service (currently GitHub Pages); the access records that service processes (such as IP addresses) fall under its own privacy policy, and the Developer does not receive them.
Article 13 (Your rights)
You can delete what is stored on your devices at any time by deleting the apps and the extension, signing out of ChatGPT, or deleting your API keys. The Developer holds none of your personal information, so there is nothing to access, correct or erase on the Developer's side. For any other question, email the address in Article 15 and you will get an answer without delay.
Article 14 (Children)
The Developer collects no personal information from anyone, regardless of age, including children under 14.
Article 15 (Privacy officer)
The Developer has designated the following privacy officer to protect your personal information and handle related complaints.
- Name: Jung Hyeon Kim (김정현)
- Email: andykimiosdev@gmail.com
Article 16 (Handling of privacy incidents)
Because the Developer stores none of your personal information, there is no user data on the Developer's side that could leak. If a privacy risk is found in the Service, the Developer will promptly announce it on the website together with what you can do, and take the steps the law requires.
Addendum
This policy takes effect on October 7, 2026.