Terms of Service

Last updated: October 12, 2026

These Terms are a binding agreement between you and Cedar Hills Studio LLC, the operator of Stack (“we”, “us”, “our”) governing your use of the Stack app (the “App”). By installing or using the App, you agree to these Terms. If you don’t agree, don’t use the App.

1. Eligibility

You must be at least 18 years old to use the App. By using it, you confirm that you are 18 or older. Stack is not designed for anyone under 18.

2. What the App is

Stack is a personal record-keeping and reminder tool. It lets you log and organize information about substances, schedules, supplies, and health metrics that you enter, and it computes conveniences (such as supply projections and “estimated level in your system” curves) from the information you provide.

3. Medical disclaimer — please read

• The App is not medical advice and is not a medical device. It does not diagnose, treat, cure, or prevent any condition.
• Using the App does not create a doctor–patient or any other professional relationship.
• All calculations, projections, “estimated level” curves, reconstitution figures, and reminders are estimates and conveniences, may be inaccurate, and must not be relied upon for medical or dosing decisions.
• Always consult a qualified healthcare professional before starting, stopping, or changing any medication, supplement, hormone, peptide, or protocol. Never disregard professional medical advice because of something you saw in the App.
• Juno and other AI features generate text automatically. Their answers can be incomplete or wrong, are general information only, and are not medical advice — everything in this section applies to them in full. Juno operates the App’s own record-keeping on your instruction; it does not and will not tell you what to take. Never act on a Juno answer without checking it with a qualified healthcare professional.
• In an emergency, contact your local emergency services.

4. No endorsement; legality; acceptable use

• The App is a neutral tool. We do not sell, supply, source, manufacture, prescribe, promote, or recommend any substance, dose, vendor, or protocol. Compound names exist only so that you can label your own records.
• You are solely responsible for the legality, safety, and appropriateness of anything you choose to track, and for how you use the App, in your jurisdiction.
• You agree not to use the App for any unlawful purpose and not to misuse it.

5. Your data and backups are your responsibility

• The App is local-first: your data is stored on your device. If your device is lost, damaged, reset, or the App is uninstalled, your data may be permanently lost.
• Backups are your responsibility. We cannot recover your data or your backup password. Make backups and store the password safely.

5b. The Stack subscription — billing terms

What you pay for. Stack is a paid app with a free trial. Logging doses in one tap, reminders, the assistant (Juno), the injection-site map and the side-effect log are part of the Stack subscription, sold monthly, every six months or yearly. There are no à-la-carte purchases, and cosmetic options such as card backgrounds are included for everyone. Everything you have logged stays yours whether or not you subscribe: without an active subscription the App remains a readable, exportable record of what you logged — your history, the doctor report and a backup file — and the features that create or change entries (logging, editing, the assistant) ask you to subscribe, and reminders pause until you do. Deleting your own data is never locked.

• Account. Using the App does not require a Stack account — you can use guest mode. If you create one, you sign in with your email via a one-time code, and you are responsible for keeping access to that email.
• Who you’re paying. Purchases made in the App are processed by the app store you bought from (Apple App Store or Google Play); the store is the merchant of record and your purchase is governed by their terms in addition to these. If we offer checkout on our website, that purchase is processed by Stripe with the subscription managed by RevenueCat, and the checkout page states who the merchant of record is. Either way, we bill nothing directly.
• Auto-renewing subscriptions. The Stack subscription auto-renews unless cancelled at least 24 hours before the end of the current period. Renewal charges hit the same payment method on file with the store. You can turn off auto-renewal or cancel at any time in your App Store / Play Store subscription settings; cancelling stops future renewals but does not refund the current period (see below).
• Free trial. New subscribers may be offered a 7-day free trial, provided by the app store as an introductory offer. The trial needs a payment method, and it converts to the paid plan you chose — at the price shown on the purchase screen — unless you cancel at least 24 hours before it ends. The purchase screen states the trial length, the price and the date of the first charge. The stores grant an introductory offer once per account; if you are not eligible, the purchase screen says so and shows the charge as immediate. You can cancel during the trial in your App Store / Play Store subscription settings (the App links there from Settings → Subscription); you keep access until the trial ends. If notifications are allowed, the App reminds you two days before the first charge; that reminder is a courtesy and not a condition of the charge. A creator or support code may separately grant a limited period of access at no charge — that grant is not a subscription, no payment method is involved, and nothing is charged when it ends.
• Lifetime access. Lifetime access is no longer sold. If you hold it — from an earlier purchase or a code — it continues: “Lifetime” means access for the supported lifetime of the App on the platform you got it on, as long as the grant remains valid with the store. It is not transferable between app stores or to other apps.
• Refunds. For store purchases, refund requests are handled by the app store under its own policy (Apple: reportaproblem.apple.com; Google: play.google.com/store/account/orderhistory). We do not process refunds directly. We may, at our discretion, ask the store to honor a refund in extraordinary cases — but the final decision is the store’s. For website purchases, except where the law requires otherwise, payments are non-refundable and cancelling does not refund the current period; this does not limit any statutory refund or withdrawal rights you may have. Contact us at hello@trackyourstack.app with any billing problem and we’ll try to make it right.
• Price changes. We may change prices at any time. Existing subscribers will see the price change only at the next renewal and will be notified by the store in line with platform rules. Continuing to use the subscription after a notified change means you accept it; you can cancel before renewal.
• Restore purchases. Reinstalling the App on the same Apple ID / Google account restores your entitlement automatically; the paywall also has a “Restore” button.

5c. Creator referral codes

The App supports creator referral codes. Redeeming a creator’s code may grant a limited period of access at no charge, or a longer free trial (for example, 14 days instead of 7). As Section 5b says, that grant is not a subscription, no payment method is involved, and nothing is charged when it ends. It does not sign you up for anything beyond the same subscription terms above. Creators do not receive any personal data about you — only an aggregate count of redemptions for payout purposes (see the Privacy Policy, Section 3b). We may rotate, expire, or revoke codes at any time without notice.

If you are a creator participating in the program, the Creator Program Terms posted at trackyourstack.app/creators govern your role; if not posted, you and we have no creator agreement.

6. License

We grant you a personal, limited, non-exclusive, non-transferable, revocable license to use the App for your own personal use, subject to these Terms and the applicable app store’s terms. You may not copy, modify, reverse-engineer, resell, or redistribute the App except as permitted by law.

7. Intellectual property

The App, its design, branding, name “Stack” (in this product context), and content (excluding your own data) are owned by us or our licensors and are protected by law.

8. Third-party services

The App uses on-device components (e.g. Google ML Kit) and features of your operating system, including its speech-recognition service if you dictate by voice. Purchases are processed through the app store or, for website checkout, Stripe, with RevenueCat managing billing. Juno requests are forwarded through Cloudflare to OpenRouter (see the Privacy Policy, Section 3b). When you share a backup or stack code, the service you choose is governed by its own terms. We are not responsible for third-party services.

9. Disclaimer of warranties

THE APP IS PROVIDED “AS IS” AND “AS AVAILABLE,” WITHOUT WARRANTIES OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, ACCURACY, AND NON-INFRINGEMENT. WE DO NOT WARRANT THAT THE APP WILL BE ERROR-FREE, THAT REMINDERS WILL ALWAYS FIRE, OR THAT ANY CALCULATION OR ESTIMATE IS ACCURATE.

10. Limitation of liability

TO THE MAXIMUM EXTENT PERMITTED BY LAW, WE WILL NOT BE LIABLE FOR ANY INDIRECT, INCIDENTAL, SPECIAL, CONSEQUENTIAL, OR PUNITIVE DAMAGES, OR FOR ANY LOSS OF DATA, HEALTH HARM, OR OTHER LOSS ARISING FROM YOUR USE OF (OR INABILITY TO USE) THE APP, EVEN IF ADVISED OF THE POSSIBILITY. OUR TOTAL LIABILITY WILL NOT EXCEED THE GREATER OF THE AMOUNT YOU PAID FOR THE APP IN THE 12 MONTHS BEFORE THE CLAIM, OR USD $0 IF THE APP WAS FREE. Some jurisdictions do not allow these limits, so they may not fully apply to you.

11. Indemnification

You agree to indemnify and hold us harmless from any claims, damages, or expenses arising out of your use of the App or your violation of these Terms or any law.

12. Termination

You may stop using the App at any time by uninstalling it. We may suspend, modify, or discontinue the App or these Terms as permitted by law. If we discontinue the App entirely, Lifetime entitlements become unenforceable — that’s the price of “supported lifetime of the App.”

13. Governing law and disputes

These Terms are governed by the laws of the United States and the state in which the operator is established, without regard to conflict-of-laws rules.

Informal first. Before filing any claim, contact us at hello@trackyourstack.app and we’ll try to resolve it in 30 days.

Binding individual arbitration. Any unresolved dispute (other than small-claims-court matters or IP-injunction claims) will be resolved by binding individual arbitration administered by the American Arbitration Association (AAA) under its Consumer Arbitration Rules, in the venue closest to the user. You and we each waive the right to a jury trial and to participate in a class action. If this arbitration clause is unenforceable in your jurisdiction, the dispute will go to a court of competent jurisdiction in the United States.

Note: this arbitration / class-waiver clause materially limits your rights. If you do not agree, you must stop using the App and uninstall it. Some jurisdictions (e.g. parts of the EU) do not permit it; in those places it does not apply.

14. Changes

We may update these Terms. Continued use after changes means you accept them. Material changes are reflected by the “Last updated” date.

15. Contact

Stack is operated by Cedar Hills Studio LLC. Contact us at hello@trackyourstack.app.