Privacy Policy

This policy explains what personal data Sona ("we", "us") collects when you use the Sona app, why we collect it, who we share it with, and how long we keep it. Sona is operated by Mikoriza Network Ltd (Company No. 17203147), registered at 71-75 Shelton Street, Covent Garden, London, WC2H 9JQ, United Kingdom. If you have questions about this policy or your data, contact us at contact@mikoriza.network.

Data we collect

We collect only what the app needs to function. We do not run advertising or analytics trackers of any kind, and we do not sell your data.

• Account data — your email address and, if you sign up with a password, a securely hashed copy of it. If you sign in with Google, we store the Google account identifier tied to your Sona account, plus the name and email address Google shares with us; we do not receive or store a profile photo.
• Profile data — the display name and timezone you set, and your interface language preference.
• Technical data — the IP address and browser/device identifier ("user agent") recorded when you sign in, and, for the mobile app, a device name you or your device supplies so a signed-in device can be identified and revoked.
• Content you create — your decks, cards (including any personal notes you add to a card, which are never shared or copied when a deck is forked), tags, and any images, audio, or video you embed in a card.
• Study activity — every review you record (rating, timing, and the resulting scheduling state), study session and quiz history. This is kept as a permanent, append-only log — individual review records are never edited or deleted — because Sona's scheduling algorithm and your activity history both depend on the full history being intact.
• AI generation data — if you use AI card generation, the file, topic description, or audio recording you submit, and the cards it produces, for as long as needed to process and let you review the result (see Retention below).
• Billing data — if you subscribe to Pro, your email address is shared with Stripe to create a billing profile, and we store the resulting Stripe identifiers. We never see or store your card number — payment is handled entirely on Stripe's own hosted pages.

Who we share data with

We use a small number of service providers to run Sona. Each only receives what it needs to do its job:

• Stripe — processes Pro subscription payments. Receives your email address and handles all payment details directly; we never see your card number.
• Resend — delivers account emails (welcome, email verification, password reset, sign-in links) to your own email address.
• OpenAI — powers AI card generation, audio transcription, and the optional spoken-audio (text-to-speech) feature. Depending on which of these features you use, this may include an uploaded file, a typed topic description, an uploaded audio recording, or the text of a card face. Card-generation requests are sent with OpenAI's data-retention option turned off; OpenAI's transcription and speech endpoints are governed by OpenAI's own standard data-handling terms, which we encourage you to review if this matters to you.
• Cloudflare (R2) — stores media you embed in cards, files you upload for AI generation, and generated spoken-audio clips. Files are always served back through our own servers, never directly from a public storage URL.
• Google — if you choose to sign in with Google, Google authenticates you and shares your name and email address with us.
• Sentry — receives diagnostic data when something goes wrong in Sona: the error itself, where in the app it happened, and internal record identifiers. It is deliberately configured not to receive your email address, your IP address, or the content of your cards.

We do not sell personal data, and we do not share it with anyone else for their own marketing purposes.

Cookies

The web app sets two cookies, both strictly necessary for it to work: one identifies your signed-in session, and one is Rails' own encrypted session cookie, which briefly holds things like a post-sign-in redirect target or which password-protected decks you've unlocked. We do not use advertising, analytics, or tracking cookies of any kind.

How long we keep data

• Your account and content are kept for as long as your account exists.
• A password sign-up that never confirms its email address is permanently deleted after roughly 7 days.
• Sign-in links expire after 15 minutes and are permanently deleted about 7 days after use (or after expiry, if never used).
• Mobile sign-in credentials ("refresh tokens") are valid for 90 days and are removed once expired.
• Files you upload for AI card generation are deleted once generation finishes (successfully or not), with a daily safety sweep as a backstop.
• Read notifications are removed 30 days after you read them; unread ones are kept until read.

Deleting your account

You can permanently delete your account at any time from Settings → Account. This immediately and permanently removes your profile, decks, cards, review history, study and quiz history, and AI generation history — there is no recovery grace period, so make sure it's what you want. If you have a live Pro subscription, we cancel it with Stripe first. A small number of things intentionally do not get deleted with your account: generated spoken-audio clips are kept as a shared, anonymized cache used by other learners studying the same content, and is never attributed back to you once your account is gone; and if someone else forked one of your public decks, their copy remains theirs.

Downgrading from Pro to Free never deletes, archives, or hides anything — your existing decks and review history keep working exactly as before, even past your plan's deck limit or per-deck card limit. These limits only ever block creating new decks or cards beyond them; Free plan limits additionally apply to AI card generation, AI audio processing, high-quality spoken audio, and media storage beyond the free allowance — nothing you already have is ever touched.

Your rights and exporting your data

You can export the cards in any deck you own as a CSV file at any time from that deck's page (front/back text only — this doesn't currently include media, personal notes, or review history). Depending on where you live, you may have additional rights over your personal data, including the right to request a copy of it, correct it, or ask us to delete it. To exercise any of these rights, contact us at contact@mikoriza.network.

Children's privacy

Sona is not directed at children under 13, and we do not knowingly collect personal data from them. If you believe a child has provided us with personal data, contact us and we will delete it.

Changes to this policy

If we make a material change to this policy, we'll update the date at the top of this page. Continuing to use Sona after a change means you accept the updated policy.

Contact us

Questions about this policy or your data: contact@mikoriza.network. Governing law: England and Wales (United Kingdom).