Effective September 12, 2026
This is the privacy policy for the Keystone app, published by KeystoneApp4Life ("we," "us," "our"). Keystone is built around a simple rule: if you don't ask the app to talk to anyone else, it doesn't. This policy explains exactly what that means in practice.
In short: If you use Keystone in manual mode, nothing about your habits, goals, or journal ever leaves your device — there's no account and nothing to collect. If you use AI Architect, we ask you to sign in with Google, but only to keep count of how many AI requests you've used — your account is never sent to the AI model, only the text you type is. If you turn on Google Drive backup, your data leaves your device only to go into your own Drive.
Information We Collect
Manual mode (no account)
If you never use AI Architect, Keystone collects nothing. Your pillars, bricks, daily check-ins, journal entries, and any backup file you export are stored only on your own device. We have no server, database, or account tied to this usage, and no way to see any of it.
AI Architect (requires signing in with Google)
The first time you use AI Architect, we ask you to sign in with your Google account. We use this only to create a record of how many AI requests you have left — a single number, tied to your account, stored on our server. We do not read your Gmail, contacts, files, or anything else in your Google account, and your account identity is never sent to the AI model.
Separately, whatever you type into AI Architect — your goal, and any follow-up feedback you give while refining a suggestion — is sent to Google's Gemini API to generate a blueprint suggestion. This text is processed by Google as our AI provider under its own terms; we don't store your AI conversations on our server beyond what's needed to keep that one session coherent while you're actively using it.
Google Drive backup (optional)
If you choose to back up to Google Drive instead of (or in addition to) keeping your data local, Keystone writes a single backup file — your pillars, bricks, journal, and settings — into a hidden, app-specific storage area of your Drive that only Keystone can see or open (Google calls this the "app data folder"). It doesn't appear in your regular Drive file list, and Keystone never gains access to your other Drive files. This requires an internet connection. Your profile photo, if you've set one, is not included in this backup and stays local to your device.
How We Use Information
The limited information described above is used only to:
- Keep track of your remaining AI Architect requests, so we can enforce free-trial and paid-credit limits;
- Send your typed goals and feedback to Google's Gemini API so it can generate blueprint suggestions;
- Store and later restore your backup file, if you've chosen Google Drive backup.
We do not use your information for advertising, we do not build behavioral profiles, and we do not sell or share it with data brokers or marketers.
Third-Party Services
Keystone relies on the following Google services to provide AI Architect and Drive backup. Each is governed by Google's own privacy terms:
- Google Sign-In & Firebase Authentication — confirms who you are before using AI Architect.
- Firebase Cloud Firestore & Cloud Functions — store your AI credit count and route your requests to Gemini server-side, so your account never has to talk to the AI model directly.
- Google Gemini API — generates the pillar and brick suggestions from the text you type into AI Architect.
- Google Drive API — stores your optional backup file, restricted to Keystone's own app-data space in your Drive.
We don't use any advertising networks, analytics SDKs, or tracking libraries in Keystone — there is nothing else collecting data on our behalf.
Data Retention & Your Choices
Data stored only on your device (manual-mode habits, journal, local backups, your profile photo) stays there until you delete it yourself or uninstall the app — we never see it, so we can't retain or delete it on your behalf.
Your AI credit record persists, tied to your Google account, for as long as you use AI Architect. If you turn on Google Drive backup, your backup file stays in your Drive until you delete it or disconnect the backup.
To request deletion of the AI credit record we hold for your account, email us at founder@keystoneapp.life from the address associated with your Google account, and we'll remove it.
Children's Privacy
Keystone is not directed at children, and we do not knowingly collect information from anyone under 13. If you believe a child has signed in to AI Architect and created an account record with us, contact us at the email below and we'll delete it.
Security
The AI credit record we hold is protected by Firebase's standard authentication and access-control rules, restricted so that only you (and our own server-side process) can ever read or write it. No method of storage or transmission is completely secure, but we don't hold anything beyond the minimum described in this policy, which limits what there is to protect in the first place.
Changes to This Policy
If how Keystone handles data changes, we'll update this page and change the effective date at the top. We'll keep the same plain-language approach rather than burying changes in legal boilerplate.
Contact Us
Questions about this policy, or a request to delete your data? Email founder@keystoneapp.life.