Mosyn Privacy Policy

Effective date: 29 July 2026

Mosyn (“Mosyn,” “we,” “us,” or “our”) is a study service made of an Android application and a remote Model Context Protocol (“MCP”) connector that a user may connect to a supported AI assistant such as Claude or ChatGPT.

This policy explains what information Mosyn collects, why, how it is protected, and what choices you have. Privacy questions and requests go to mosyn@lycatra.com.

1. Information we collect

Account and authentication information

When you sign in through Google we receive and store your Google account identifier and verified email address. You may instead ask us to email a single-use sign-in link. We store the verified identity, short-lived sign-in transaction records, and the minimum delivery and abuse-prevention records needed to authenticate you, associate your devices and assistant connections with the right account, and prevent unauthorised access. We never receive or store your Google or email password.

Study content you create

We store the content you create, or direct an AI assistant to create, in Mosyn: set names and descriptions, card text, source material you supply, custom study-experience code and configuration, and related metadata.

At your direction the service may fetch an image or audio file from a URL that you or your assistant chose, check and resize it, and store it with your study content. You and your assistant should only supply content and media sources you are entitled to use.

Your study content is private to your account. Mosyn has no sharing, publishing, or discovery feature, and we do not disclose your study content to other Mosyn users.

Study progress

Your study history — which cards you answered, when, and in what order — is written on your phone and stays there. It is not uploaded to our servers, and a connected assistant cannot read it.

Device-local age choice

Before Mosyn offers cloud sign-in, a connected assistant, or a purchase, the Android app asks you to choose one of three age groups: under 13, 13–15, or 16 and older. The choice is stored only in the app's device-local preferences. We do not receive it, upload it, associate it with an account, or use it for advertising.

Mosyn is not intended for children under 13. In version 1, people aged 13–15 can use local and offline study features but cannot create a cloud account, connect an assistant, or make a purchase. Those cloud and paid features are available only to people aged 16 or older, subject to any higher minimum age or other requirement imposed by local law.

Purchase and entitlement information

For purchases made through Google Play or the checkout offered by the direct Android edition, we receive and store what is needed to verify and maintain your access: the payment provider, product and purchase identifiers, entitlement status, and renewal, expiry, cancellation, refund, or revocation state. Google Play or Lemon Squeezy processes the payment. We never receive or store card or bank-account numbers.

Custom-experience diagnostics

Custom study experiences run in a restricted Android WebView. When an experience logs console output or throws an error, a short buffer of those lines can be read back by your own connected assistant so it can find and fix the problem without you having to describe it. Each line carries a level, a message, and optionally a file name and line number. These lines are held briefly for that purpose and are not used for advertising or for profiling across users.

Console output should not contain tokens, passwords, or unrelated personal information. Avoid putting secrets into custom experience code or content.

Technical and security information

Our servers necessarily process limited request and security information — timestamps, network addresses, authentication events, and error information — to serve requests, protect accounts, prevent abuse, and keep the service reliable.

What we do not collect

• No location data, precise or approximate.
• No advertising identifier, and no advertising, attribution, or analytics SDK. The Android app ships no third-party analytics or crash-reporting library.
• No contacts, calendar, SMS, call logs, photos from your device gallery, browsing history, or health data.
• No birth date. The coarse age group selected in the Android app stays on the device.
• No access to your AI assistant's chat history, memory, uploaded files, or any conversation content beyond the specific input a tool call carries.

2. How we use information

• Create and authenticate your account.
• Synchronise sets, cards, media, and custom experiences between your devices and your connected assistant.
• Fetch and process media when you direct us to.
• Verify purchases and apply, restore, change, or remove entitlements.
• Enforce free-plan and paid-plan limits.
• Return custom-experience console output to your own assistant for debugging you asked for.
• Provide support, investigate errors, secure the service, and prevent fraud and abuse.
• Comply with applicable law and enforce our terms.

We do not use personal information for third-party advertising, and we do not sell personal information.

3. How information is disclosed

We do not sell personal information and we do not serve ads. We disclose information only as needed in these circumstances:

• Service providers. Cloudflare processes and stores data on our behalf to provide compute, database, object storage, coordination, networking, and security services.
• Email delivery. Resend processes your email address and delivery metadata when you request a single-use sign-in link.
• Direct-edition payments. Lemon Squeezy processes checkout, tax, payment, refund, and subscription information for purchases made outside Google Play.
• AI assistants you connect. When you connect the MCP server to Claude, ChatGPT, or another compatible client, your requests, the study data a tool returns, and custom-experience diagnostics pass through that provider as needed to carry out your request. That provider handles the information under your relationship with it, its own terms, and its own privacy policy.
• Google. Google processes browser-based Google sign-in and Google Play purchases. The Play Billing Library also uses Google's internal transport for billing-service diagnostics. Mosyn requests no location permission and does not call a location API. We exchange only the authentication, billing, diagnostic, and purchase-verification information those services require.
• Legal and safety. We may preserve or disclose information where reasonably necessary to comply with law, legal process, or an enforceable government request; to protect users, the public, or our rights; to investigate fraud or a security incident; or to establish, exercise, or defend legal claims.
• Business transfer. If the service is involved in a merger, acquisition, financing, reorganisation, insolvency, or sale of assets, information may transfer subject to applicable law and any required notice.

4. Storage and international transfers

Mosyn runs on Cloudflare infrastructure. Your information may be processed or stored in the United States and the European Union, and requests may be handled by Cloudflare's global network. That can involve transferring information to countries whose data-protection laws differ from those where you live. Where the law requires a transfer mechanism, we rely on the mechanism identified in our agreement with our infrastructure provider.

5. Retention

We keep your account information, study content, stored media, and entitlement records while your account is active and for as long as we need them to provide the service.

• Sign-in transactions and email links — expire after ten minutes and cannot be used again after completion.
• Sync history — the pointer log that lets a device catch up after being offline is pruned after 90 days.
• Custom-experience console output — held only as a short rolling buffer per experience and overwritten as new output arrives.
• Deleted content — removed from active systems on deletion, subject to the limited exceptions below.

After a completed deletion request we may retain a limited amount of information where we must for legal, tax, accounting, fraud-prevention, security, dispute-resolution, or backup-integrity reasons. Anything retained stays protected and is used only for the reason it was retained.

6. Account and data deletion

You can delete an individual set, card, stored image, or custom experience from its own menu in the Android app. That removes the selected content from active cloud systems and syncs the deletion to your other devices without deleting your account. The public data-deletion page also explains how to request deletion of selected content if you cannot use the app.

You can delete your Mosyn account in any of these ways:

1. In the Android app, open Settings and choose Delete account, then confirm.
2. Open the public account-deletion page for instructions that work without the app.
3. Email mosyn@lycatra.com from the address on the account and ask us to delete it.

Deletion removes the account rather than freezing it. We delete your sets, cards, stored media files, custom experiences, sessions, and connected-assistant grants, and we remove the per-account server state that supports live sync — subject only to the limited retention described in section 5. We may take reasonable steps to confirm that a requester controls the account before deleting it.

Disconnecting the Claude or ChatGPT connector revokes that client's future access but does not by itself delete your account. Uninstalling the Android app does not by itself delete server-side data either.

7. Security

We use administrative, technical, and organisational safeguards designed to protect information, including encrypted transport for all network traffic, hashed session tokens, per-account scoping of every query, and separation between accounts. Custom experience code runs in a deny-by-default WebView sandbox designed to block network access and to restrict what the native bridge exposes.

No security measure is perfect. Protect your email, Google, and AI-assistant accounts, and report suspected unauthorised access to mosyn@lycatra.com.

8. Your choices and rights

Depending on where you live, you may have the right to request access to, correction of, deletion of, restriction of, or objection to processing of your personal information, to request portability, or to withdraw consent where processing is based on consent. Contact mosyn@lycatra.com to exercise a right that applies to you. We may verify your identity before acting on a request.

You can also disconnect the connector in your AI assistant's own settings, which revokes its access; manage or cancel a subscription through the provider that sold it; and delete your account using the methods in section 6, which revokes every assistant grant on the account.

Where the right applies, you may also complain to your local data-protection authority.

9. Children's privacy

Mosyn is not directed to children under 13. The Android app's device-local age gate prevents people who select under 13 from using cloud accounts, connected assistants, or purchases. People who select 13–15 can use local and offline study in version 1, but those same cloud and paid features remain unavailable. Mosyn does not receive the selected age group.

If you are a parent or guardian and believe a child provided personal information unlawfully, contact mosyn@lycatra.com so we can investigate and delete it.

10. Third-party services

Google sign-in, Google Play, Resend, Lemon Squeezy, Claude, ChatGPT, the websites your assistant selects when you ask it to find an image, and Cloudflare each have their own terms and privacy practices. Mosyn does not control third-party websites, or an assistant provider's independent handling of your conversation. Review those providers' policies before connecting, purchasing, or directing the service to fetch third-party content.

11. Changes to this policy

We may update this policy when the product, the law, or our data practices change. We will post the updated policy at this URL, change the effective date, and give additional notice where the law requires it. A material change will not retroactively authorise a materially different use of information we already collected without any consent the law requires.

12. Contact

Privacy and support: mosyn@lycatra.com
Publisher: Milo Yvan Presedo

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