Second AI Brain Privacy Policy

Effective date: September 26, 2026

Second Brain is designed to keep your personal memory and knowledge under your control. This policy explains what the app processes and when information may leave your device.

Version boundary: Version 1.0.5 is available on the App Store. The hosted-AI disclosures below apply to 1.0.5 and later. Devices still running version 1.0.4 have different AI and Gmail behavior, described under Version 1.0.4. Features and data practices depend on the version installed on your device.

Version 1.0.5 and later: data stored on your device

Memories, knowledge items, attachments, local indexes, retrieval data, preferences, and task state are stored on your device, except for any selected data you choose to synchronize through your private iCloud account. The app does not contain or ask you to supply a model-provider API key. Your complete local library is not uploaded to the developer.

Hosted AI and its precise privacy boundary

Before any hosted AI content is sent, the app asks for separate, explicit permission. If you decline or withdraw it, local features remain available and hosted AI content requests are blocked. Depending on the task you choose, the content sent can include entered text, voice transcripts, selected knowledge documents, and relevant excerpts from memories, reminders, or context sources you enabled, such as calendar events, location, photo descriptions, or health summaries. The app does not upload your entire library or Contacts address book for AI processing.

When you request an AI feature, the text needed for that operation is sent over TLS to a separately deployed Cloudflare relay operated for Second Brain, then to MiniMax's China-region API for inference. The relay necessarily processes the request and response in memory; it is not end-to-end encrypted from the phone to MiniMax and cannot honestly be described as unable to see plaintext. The relay does not save prompts, answers, or uploaded documents in its database or content logs, and does not offer a human content-review dashboard. MiniMax receives the inference content. Its API Privacy Policy governs its processing and retention; we cannot promise zero retention by MiniMax. Do not submit information that must never leave your device.

The relay checks subscription status with Apple using the original subscription transaction identifier and a random app-account token. Its quota store retains the transaction identifier as a storage key, random operation/document/request identifiers, document character counts, plan periods, and usage counters needed to enforce limits; it does not retain the app-account token. It does not forward your app-account token, subscription identifier, email address, or other account identity to MiniMax. Cloudflare and Apple may process service metadata under their own terms. The model credential is held as a Cloudflare secret and can be rotated without an app update. AI access requires an active trial or subscription; expiry does not remove your existing local data.

Email features discontinued

Version 1.0.5 and later do not offer Gmail or IMAP account connection, mailbox refresh, mail suggestions, reply drafts, or mail AI processing, and do not request new Gmail data. Previously connected accounts, credentials, and mail-derived records may remain locally on devices upgraded from an older release, but are inactive: the app cancels scheduled mail tasks and does not send that legacy content to the hosted model. Items identified as email messages by the share extension, and legacy mail-share queue items, are not processed by the mail AI feature; a failed import may remain locally. If you deliberately share plain text from another app, the app treats it as an ordinary text import. You can revoke the old app authorization in your Google Account. The developer cannot remotely access or remove old device-local records or Keychain items.

Data protection and security controls

Network connections to the hosted relay use HTTPS/TLS; credential-bearing requests do not follow redirects. Legacy mail credentials, if present after an upgrade, remain in device Keychain storage but are not used by the discontinued feature. Legacy mail records remain in the app sandbox and are not synchronized by this app's private iCloud feature.

Apple services and permissions

When you enable a related feature, the app may use Apple services and permission-controlled data such as iCloud/CloudKit, Calendar, Notifications, Location, Microphone, Speech Recognition, Camera, Contacts, Health, Weather, App Intents, widgets, and Spotlight. Permissions can be reviewed or revoked in system Settings. Health data is read-only; the app does not write Health data.

Contacts access is used only after you choose a contact action: the app looks up a named contact and phone number on your device so you can confirm a call. It does not upload the address book, the lookup result, or the selected phone number to our relay or MiniMax. Revoking Contacts access does not prevent use of local memories or knowledge.

Imported content and external websites

If you ask the app to import a link or media, it connects to that website to retrieve the content you selected. Network requests reveal ordinary connection information, such as your IP address, to the destination website. Weather alerts may be retrieved from Apple Weather and public weather sources.

Cross-device sync

If you enable iCloud synchronization, selected app data is stored in your private iCloud container and handled according to Apple's iCloud terms. Cross-device sync is optional.

Data collection by the developer

The developer does not use Second Brain data for advertising, tracking, data brokerage, or developer analytics. The app does not contain third-party advertising SDKs. Subscription identifiers and usage counters are collected to provide and protect the hosted service; model content passes transiently through the relay as described above.

Retention and deletion

You can delete memories and knowledge inside the app. You can also remove the app and its local data through iOS. Data synchronized through iCloud can be managed through your Apple account and the app's synchronization features. The relay does not retain model content; MiniMax's processing and retention are governed by its own terms. Subscription usage records remain for service operation and abuse prevention; contact us to request access or deletion where applicable.

Version 1.0.4: user-configured AI and Gmail

Version 1.0.4 does not use the developer's hosted AI relay or collect subscription identifiers and usage counters. It ships without a model provider, endpoint, or API key. If you configure an AI service, the API key is kept in the device Keychain and bounded content needed for a requested memory, knowledge, context, or planning operation is sent directly to your configured endpoint, subject to that provider's privacy terms.

If you explicitly connect Gmail in version 1.0.4, the app requests gmail.readonly and reads inbox sender and recipient fields, subject, Gmail-produced snippet, message and thread identifiers, dates, and attachment metadata; it does not download full message bodies or modify, delete, or send email. OAuth tokens are stored in the device Keychain. Mail evidence, suggestions, and reply drafts are stored in the app's local database, not its memory or knowledge libraries, and are not synchronized through the app's private iCloud feature. After in-app disclosure and consent, only the subject and bounded snippet needed for requested mail understanding are sent directly to the LLM endpoint you configured. The full body, OAuth token, sender and recipient fields, and attachments are not sent to that model. The developer does not receive Gmail content or offer human access to it.

Google user data is not sold, used for advertising, credit decisions, data brokerage, or training general-purpose AI models. You can disconnect Gmail and delete local tokens and imported mail records in version 1.0.4, revoke access in your Google Account, or remove the app and its local data. Second Brain's use and transfer of information received from Google APIs adheres to the Google API Services User Data Policy, including the Limited Use requirements.

Children

Second Brain is a general productivity app and is not directed specifically to children.

Contact

Privacy questions: support@prismsai.org

第二大脑隐私政策

生效日期：2026 年 9 月 26 日