Solastone Privacy Policy

Draft — effective date to be set at launch. Replace the bracketed placeholders before publishing.

The short version: Solastone works fully on your phone, with no account. If you choose to sign in, what you keep in the app is backed up to your account so you can restore it or use it on another phone; your thought logs are encrypted on your phone before they are uploaded. If you ask your stone for a letter, a short summary of your check-ins (never your notes or thought logs) is sent to Anthropic to write it. If you ask your stone to write mantras for you, the words you type, the kind of hope you picked, and the name of your recent state are sent to Anthropic to write them. We don't sell or share your data, and there is no analytics, advertising, tracking, or crash reporting.

What Solastone keeps

Solastone stores the following in a private database inside the app, on your phone:

Check-ins — the state you chose (green, yellow, red, purple), the time, whether you marked green as thriving, the minutes you had, where you were (home, work, traveling), the tool you used, your answers to "Did it help?" and "Where are you now?", and any notes you write.
Feelings — any words you choose for how you feel, and where in the body you felt it.
Thought logs — anything you write in the guided thought log or Let anger move.
Set down — what you let go is set aside in the app on this phone only, so you can bring it back or let it go for good from Settings → Set down; it is never backed up, synced, or uploaded, even when you're signed in.
Your toolkit — tools you add yourself, and which tools you've favorited or hidden.
Your words — feeling words you add to your own library.
Your states — what you write about how each state feels in your body.
Your shelf — which items (like an acupressure ring) you've checked as having.
Settings — reminder times, breath pace, sound choices, and the haptics preferences.
Letters from your stone — letters you choose to keep, on this phone only (see "Letters from your stone" below).
Your mantras — mantras you add, write, or keep, which one is current, and where you've chosen to see it (see "Mantras" below).

Lock Solastone (Settings → Privacy) is optional: it asks for your phone's own unlock — your face, your fingerprint, or your passcode — before the app opens, and the phone does the checking, so Solastone never sees your face, fingerprint, or passcode, and nothing about the lock leaves the phone.

Without an account

Nothing above leaves your phone through Solastone. Like other app data, it may be included in your phone's own backups (for example iCloud or Google device backup), which are governed by Apple's or Google's terms.

With an account (optional)

Signing in is never required. If you sign in, Solastone stores:

Your account — your email address, a user id, and the way you sign in (emailed code, Apple, Google, or password). If Apple or Google shares your name, it is kept as your account's display name. If you use Sign in with Apple and hide your email, we only see Apple's relay address. Passwords are handled by Firebase Authentication; we never see them.
Your backup — everything listed under "What Solastone keeps", so it can be restored. What stays on each phone: anything set down, and the day the stone last settled on screen.
Thought logs, encrypted on your phone — before a thought log is uploaded, the app encrypts everything in it (the words, the kind of entry, where it was felt, and which check-in it belongs to) with AES-256-GCM. Our servers receive only the encrypted entry plus its id, time, and whether it was deleted.
Sign-in codes — when you ask for a code, we keep a one-way hash of the code, a hashed form of your email address, the number of tries, and when codes were sent (to limit repeated requests). A code works once, expires after 10 minutes, and these records are removed automatically.

Your other backed-up data (check-ins, notes, feelings, your toolkit, shelf, and settings) is protected in transit with HTTPS and encrypted at rest by Google Cloud, but it is not encrypted by the app itself the way thought logs are.

How the thought-log key works

Each account has its own thought-log key. It is created on our server, stored only in encrypted ("wrapped") form using Google Cloud Key Management Service, and sent only to you when you are signed in. Your phone keeps it in its secure keychain or keystore and never includes it in device backups.

We chose this so you can restore your thought logs on a new phone without remembering a separate passphrase. It also means Solastone's service could technically decrypt your thought logs. We don't, access to the key service is restricted to the service itself, and its use is recorded in Google Cloud's audit logs.

Where it's kept, and who helps

Google Cloud / Firebase (Firebase Authentication, Cloud Firestore, Cloud Functions, Cloud Key Management Service) stores your account and backup in the United States.
Firebase App Check, with Apple's App Attest or Google Play Integrity, confirms that requests to sign in, fetch your thought-log key, write a letter from your stone, write mantras, or delete your account come from the real Solastone app. Your phone sends a short-lived token vouching for the app and device; it carries nothing about you or your data and is used only to block abuse.
Resend sends the emails containing sign-in codes. It receives your email address and the code.
Anthropic writes letters from your stone and mantras, only if you ask. For a letter it receives the summary described below; for mantras, only what is listed under "Mantras". It never receives your name, email address, or account id.
Apple or Google, if you choose to sign in with them, confirm who you are under their own privacy policies.

These providers process data only to run Solastone for you. We don't sell your data, share it for advertising, or use it to track you.

On a shared phone

Signing out keeps everything on the phone and stops backing up. If a different account later signs in on the same phone, what's on the phone is backed up to that account too.

Letters from your stone

Letters are optional and need an account. Now and then, your stone can write you a short letter about what it has noticed in your check-ins. Nothing is sent until you have seen what will be sent and tapped "Write my letter", and nothing is sent again unless you ask for another letter.

What is sent, each time you ask for a letter. Your phone builds a summary of your last six weeks of check-ins:

how often you chose each state, week by week ("this week", "last week"), by time of day (morning, afternoon, evening, night), and by place (home, work, traveling);
the names of the practices from Solastone's toolkit you used, the state you were in, and whether you said they helped (a practice you made yourself is sent only as "a practice of your own", never by its name);
which state you were in before and after a practice;
how many moments you marked as thriving, by time of day and place;
whether red came up on three or more days in a row recently;
feeling words, only if you turn on "Include feeling words", and only words from Solastone's own list.

Never sent: your notes, thought logs, anything you set down, your playlists, where in the body you felt something, feeling words you added yourself, the names of practices you made, your name or email address, or exact dates and times.

Who handles it. Solastone's server (Google Cloud Functions) checks the summary and passes it to Anthropic, whose Claude model writes the letter, then returns the letter to your phone. Our server doesn't store or log the summary or the letter. To limit how often letters are written (one a day, eight in 30 days), it keeps the times you asked for a letter, linked to your account id; those times are removed when they are more than 30 days old, and when you delete your account.

Anthropic processes the summary as our service provider, only to write your letter, and receives no email address, name, or account id. Under Anthropic's terms for its API, it does not use the summary or the letter to train its models. Anthropic deletes API inputs and outputs within 30 days, unless it needs to keep them longer to enforce its usage policies (content flagged as violating them can be kept for up to 2 years) or the law requires it. See Anthropic's privacy policy.

The letter stays on your phone. If you tap Keep, it's saved in the app's private database on this phone only: it is never backed up or synced, even when you're signed in. Share hands the text to your phone's share sheet; where it goes is up to you.

Turning it off. Settings → Your data → Letters from your stone. When it's off, nothing is sent. The choice (and "Include feeling words") belongs to this phone and never syncs, so turning letters on for one phone doesn't turn them on for another. Letters you kept stay until you remove them, or until Settings → Erase all check-ins removes them with everything else.

A letter is a reflection written by an AI model from the summary above. It isn't advice or care, and it can get things wrong.

Mantras

Your mantras are short phrases you keep in Settings → Your mantras. The list starts with a general one, "All is well in my world." The mantras you add, edit, write, or keep, which one is current, and whether it shows while breathing or on the home screen are stored in the app on your phone, like your notes. If you're signed in, they're backed up to your account and synced to your other phones, like the rest of your backup. Settings → Erase all check-ins removes them with everything else.

The suggestions under "Find one for what you're hoping for" come from a list built into the app. Browsing or adding them sends nothing anywhere.

Write me one (optional, needs an account). If you ask your stone to write mantras for you, Solastone's server (Google Cloud Functions) passes exactly three things to Anthropic, whose Claude model writes three short mantras and returns them to your phone:

the words you typed under "What you're hoping for" (up to 200 characters), as you wrote them;
the kind of hope you picked, if you picked one (for example "Calm" or "Letting go");
the name of the state from your most recent check-in (green, yellow, red, or purple), only if it was within the last six hours.

Never sent: your check-ins or their times, notes, thought logs, anything you set down, your other mantras, your name, email address, or account id. Because what you type is in your own words, please leave out anything you wouldn't want to send, like names or contact details.

Nothing is sent until you've seen what will be sent and tapped "Write me some" the first time, and nothing is sent again unless you ask. Our server doesn't store or log your words or the mantras. To limit requests (ten a day), it keeps the times you asked, linked to your account id; those times are removed after about two days, and when you delete your account. Anthropic handles your words as it does letters (above): as our service provider, only to write your mantras, without using them to train its models, and deleting them within 30 days unless its usage policies or the law require otherwise.

Mantras you tap Keep on are saved like any other mantra. Ones you don't keep are gone when you leave the screen.

Turning it off. Settings → Your data → Let your stone write mantras. When it's off, nothing is sent until you agree again. The choice belongs to this phone and never syncs.

Mantras written by an AI model can miss the mark. They aren't advice or care.

Reminders

If you turn on reminders, your phone schedules them locally. No push-notification server is involved, and no device token is created or sent anywhere.

Motion

Solastone may read your phone's orientation to light the stone on screen as you tilt it. These readings are used in the moment for drawing only; they are never stored or shared, and no motion or fitness permission is requested.

Share a summary is always your choice: the app puts together a PDF or plain text on your phone from only what you select, shows it to you first, and hands it to your phone's own share sheet — Solastone uploads nothing, and where it goes is up to you.

Writing to us, and reporting what your stone wrote

Settings → Help → Write to us opens a draft in your own email app, addressed to support@solastone.co. The draft holds the app's version and build, your phone's operating system and version, and a general model (like "iPhone"); never your check-ins, notes, account, or your phone's name. Nothing is sent until you send it from your email app.

You can report a letter from your stone, or a mantra your stone wrote, with Report. It opens a draft the same way, with the reason you chose and any note. The words of the letter or mantra go in only if "Include the text" is on (it starts on, and you can turn it off). We use what you send only to answer you and to improve Solastone, and we keep it in our email, not in the app's systems.

Guide videos

Some tools offer a guide video. Opening one leaves Solastone and opens YouTube (in the YouTube app or your browser). YouTube's own privacy policy applies there; Solastone shares nothing with YouTube.

Links to other apps and products

Some tools and shelf items show a quiet link to another app (like Aura, Headspace, or Calm) or to a place to find an item. These open external sites or apps with their own privacy policies. Solastone doesn't share your data with them and isn't paid for these links. You can turn them all off in Settings.

The website

solastone.co has no analytics, advertising, tracking pixels, or cookies. Its fonts are loaded from Google Fonts, so your browser's request for them (including your IP address) reaches Google under Google's privacy policy.

Waitlist. If you join, we keep your email address, what you asked to hear about (the app, the stone, or both), and when you joined, in Google Cloud Firestore. Resend sends you one short confirmation, and later the updates you asked for. Reply "unsubscribe" to any email, or write to support@solastone.co, and we'll remove you.
Write to us. If you send the contact form, we keep your name (if you give one), email address, topic, and message in Google Cloud Firestore, and Resend emails it to support@solastone.co so a person can reply. You'll get a short confirmation that doesn't repeat your message. We use it only to answer you, and delete it on request. Please leave out health details you wouldn't want in an email.
Keeping the forms from being abused. To limit spam, we keep hashed (not readable) forms of your IP address and email address with the times forms were sent. These records are removed automatically after a few days.

Permissions

Notifications (optional) — only if you turn on reminders.
Face ID, Touch ID, or fingerprint and face unlock (optional) — only if you turn on Lock Solastone. The check happens on your phone; the app is only told whether it passed.

Solastone does not use location, camera, microphone, contacts, photos, HealthKit or Health Connect, or advertising identifiers.

Deleting your data

Check-ins and thought logs: Settings → Erase all check-ins removes every check-in, note, thought log, everything set down, every kept letter, and your mantras from your phone and, if you're signed in, from your backup. Individual thought logs can be deleted from the Thought log screen, which also removes them from your backup.
Your account: Settings → Account → Delete account erases your account, everything backed up to it, your thought-log key, and the record of when you asked for letters or mantras, right away. Your phone keeps its own copy; delete the app to remove that too.
Without the app: email support@solastone.co from the address on your account and we will delete the account and its backup.
Deleted data may remain in Google Cloud's systems for a short period while their standard deletion completes.

Children

Solastone is not directed at children under 13, and we do not knowingly create accounts for them.

Not medical care

Solastone is a wellness tool. It does not diagnose, treat, or monitor any condition and is not a substitute for professional care. If you are in crisis, contact local emergency services.

Changes

If this policy changes, the updated version will be posted at https://solastone.co/privacy with a new effective date.

Contact

Solastone LLC — support@solastone.co