Terms of Use & End User License Agreement

For Gimbal: ADHD Test & Focus · Last updated: September 12, 2026

These Terms of Use (which include the End User License Agreement, together the "Terms") are an agreement between you and Muzaffer Uyar and Hicret Uyar, independent software developers based in Türkiye, operating together under the trade name muzo.dev ("we", "us", "our"), for the use of the mobile application Gimbal: ADHD Test & Focus ("Gimbal", "the app").

By downloading, installing or using Gimbal, you accept these Terms. If you do not accept them, do not use the app. If you are under the age at which you can enter a binding agreement where you live, a parent or guardian must accept these Terms on your behalf.

1. Licence

We grant you a limited, non‑exclusive, non‑transferable, non‑sublicensable, revocable licence to install and use Gimbal on a device you own or control, for your own personal, non‑commercial use. Gimbal is licensed, not sold, to you.

This licence does not permit use of Gimbal to assess, screen or monitor other people in a professional, clinical, educational, employment or research context. If you want to use Gimbal in such a setting, contact us first.

2. Restrictions

You agree not to:

• Reverse engineer, decompile, disassemble or attempt to derive the source code of the app, except to the extent this restriction is prohibited by applicable law
• Modify, adapt, translate or create derivative works of the app
• Distribute, sublicense, rent, lease, sell or otherwise make the app available to third parties
• Remove or alter any copyright, trademark or other proprietary notice
• Circumvent the licensing checks that separate the free features from Pro, or use unauthorised means to unlock Pro
• Use the app in a way that breaks applicable law, or that interferes with its normal operation

3. What Gimbal is, and what it is not

Gimbal provides self‑report questionnaires and cognitive performance tasks, records the results on your device and shows you how they change over time, together with a focus timer and planning tools.

Gimbal does not provide a diagnosis, a clinical assessment, treatment, therapy or medical advice, and its output must not be used to make medical decisions. Scores are indicative only and are affected by sleep, stress, caffeine, medication, environment, and by your device's screen and touch response. Do not start, stop or change any treatment because of something the app showed you. See the Medical Disclaimer.

4. Free features

The following are available permanently at no cost, with no account and no advertising: the full ADHD profile and its result, two performance tests, the focus timer with all three session lengths, note parking, the daily check‑in, tasks and one project.

5. Gimbal Pro — subscriptions and purchases

Gimbal Pro unlocks all eight performance tests, repeat measurements with progress over time, the detailed executive‑function and chronotype maps, personal suggestions and experiments, and unlimited projects. Pro is offered in two forms:

• An auto‑renewing subscription, billed for the period shown at purchase (for example monthly or annual)
• A one‑time lifetime purchase, paid once and not renewed

5.1 Price and payment

Prices are displayed in the app and on your store page in your local currency before you confirm, and include any taxes the store collects on our behalf. Payment is charged to your Apple or Google account when you confirm the purchase. We never see or handle your card details.

5.2 Auto‑renewal

A subscription renews automatically for the same period at the then‑current price unless you cancel it at least 24 hours before the end of the current period. The store charges the renewal within the 24 hours before the period ends. Your subscription continues until you cancel it — there is no fixed number of periods.

5.3 How to cancel

You cancel where you bought it, not in the app:

• iOS: Settings → your name → Subscriptions → Gimbal → Cancel Subscription
• Android: Google Play → profile icon → Payments & subscriptions → Subscriptions → Gimbal → Cancel

Deleting the app does not cancel a subscription. After cancellation you keep Pro until the end of the period already paid for, and then the app returns to its free features. Your data stays on your device either way.

5.4 Free trials and introductory offers

Where a free trial or introductory price is offered, its length and price are shown before you confirm. Unless you cancel at least 24 hours before the trial ends, it converts to a paid subscription at the standard price. If you buy a subscription while a free trial is running, the unused part of the trial is forfeited.

5.5 Lifetime purchase and restoring

The lifetime purchase is a single payment tied to the store account you bought it with. "Lifetime" means the supported lifetime of the app and does not oblige us to operate or update Gimbal indefinitely. Reinstall the app or move to a new device on the same store account and use Restore purchases to unlock Pro again. A purchase made on the App Store cannot be restored on Google Play, or the other way round, because the two stores hold separate receipts.

5.6 Refunds

Purchases are made through Apple or Google, so refunds are handled by them under their policies, not by us:

• Apple: reportaproblem.apple.com
• Google Play: Google Play refund request

If you live in the EU, the UK or another jurisdiction with a statutory right of withdrawal for digital content, that right applies as your local law provides; note that it can be lost once delivery of the digital content begins with your express consent. Your mandatory consumer rights are not affected by these Terms. We are happy to support a refund request you make to the store — write to us and say what happened.

5.7 Price changes

We may change prices for future periods. The store will notify you in advance as its rules require, and a subscription price increase does not take effect until you have had the opportunity to cancel.

6. Your data and your responsibility for it

Gimbal stores your answers, results, notes, tasks and sessions only on your device. We hold no copy and have no access. This means:

• If you lose, reset or wipe your device, or uninstall the app, your data is gone and we cannot recover it
• Keeping a backup is your choice and your responsibility — see Your Data & Deletion
• Anyone who can unlock your device can read your Gimbal data

How the app handles data is described in the Privacy Policy, which forms part of these Terms.

7. Updates and changes to the app

We may release updates that add, change or remove features, and some updates may be necessary to keep using the app. Free features may change over time, but we will not move a feature out of the free tier that was central to it without saying so in the app. We may discontinue Gimbal; if we do, we will give reasonable notice in the app so that you can export or record what you need.

8. Intellectual property

Gimbal and everything in it — code, design, text, test implementations, scoring logic, graphics and audio — belong to Muzaffer Uyar and Hicret Uyar (muzo.dev) or their licensors, and are protected by copyright and other laws. The questionnaires and cognitive paradigms Gimbal implements derive from published research; the implementations, scoring and presentation in the app are ours. No rights are granted beyond those stated in these Terms.

The content you create in the app — your answers, notes, tasks and results — is yours. We claim no rights in it and never receive it.

9. Third‑party services

Purchases are processed by Apple or Google and validated through RevenueCat, Inc. Their terms and privacy policies apply to that part of the service. We are not responsible for those services' availability or for the platform's own billing decisions.

10. Disclaimer of warranties

To the maximum extent permitted by law, Gimbal is provided "as is" and "as available", without warranties of any kind, whether express, implied or statutory, including merchantability, fitness for a particular purpose, accuracy, and non‑infringement. We do not warrant that the app will be uninterrupted or error‑free, that results are accurate or clinically valid for your situation, or that it is suitable for any medical, diagnostic, employment, educational or legal purpose.

11. Limitation of liability

To the maximum extent permitted by law, we are not liable for indirect, incidental, special, consequential or punitive damages, nor for loss of data, profits, revenue or opportunity, arising from or related to your use of Gimbal — including any decision you make on the basis of a result the app produced.

To the maximum extent permitted by law, our total aggregate liability for any claim relating to Gimbal is limited to the amount you paid us for it in the twelve months before the claim, which for free use is zero.

Nothing in these Terms excludes or limits liability that cannot be excluded or limited by law, including liability for death or personal injury caused by negligence, for fraud, or under mandatory consumer protection law.

12. Termination

This licence ends automatically if you breach these Terms; you must then stop using Gimbal and uninstall it. You may end it at any time by uninstalling the app. Sections 6, 8, 10, 11 and 15 survive termination.

13. Additional terms for the Apple App Store

If you obtained Gimbal from the Apple App Store, the following applies and prevails over anything inconsistent with it:

• This agreement is concluded between you and muzo.dev (Muzaffer Uyar & Hicret Uyar) only, and not with Apple. Apple is not responsible for the app or its content.
• Apple has no obligation whatsoever to provide any maintenance or support for the app.
• If the app fails to conform to any applicable warranty, you may notify Apple and Apple will refund the purchase price, if any. To the maximum extent permitted by law, Apple has no other warranty obligation with respect to the app.
• Apple is not responsible for addressing any claim by you or a third party relating to the app, including product liability claims, claims that the app fails to conform to a legal or regulatory requirement, and claims under consumer protection or similar legislation, including in connection with the app's use of HealthKit or HomeKit frameworks (which Gimbal does not use).
• Apple is not responsible for the investigation, defence, settlement or discharge of any third‑party intellectual property infringement claim relating to the app.
• You represent that you are not located in a country subject to a U.S. Government embargo or designated as a "terrorist supporting" country, and that you are not listed on any U.S. Government list of prohibited or restricted parties.
• Apple and Apple's subsidiaries are third‑party beneficiaries of these Terms and, upon your acceptance, will have the right to enforce them against you.
• Your use of the app must comply with the Apple Media Services Terms and Conditions, including the Usage Rules.

14. Additional terms for Google Play

If you obtained Gimbal from Google Play, these Terms apply in addition to the Google Play Terms of Service. Google is not a party to these Terms and is not responsible for the app. Subscription management, billing and refunds follow Google Play's rules.

15. Governing law and disputes

These Terms are governed by the laws of the Republic of Türkiye, without regard to conflict of law rules, and the courts and enforcement offices of Türkiye have jurisdiction. If you are a consumer resident in the EU, the UK or another jurisdiction whose law gives you the protection of mandatory local rules, those protections continue to apply to you and you may also bring proceedings in your country of residence. EU consumers may use the European Commission's online dispute resolution platform; consumers in Türkiye may apply to the consumer arbitration committees (tüketici hakem heyetleri) or consumer courts.

16. Export compliance

You agree to comply with applicable export control and sanctions laws when using Gimbal, and not to use it where doing so would breach them.

17. Changes to these Terms

We may update these Terms. The "Last updated" date changes with them and material changes will be announced in the app before they take effect. Continued use after that means you accept the updated Terms; if you do not, stop using the app and cancel any subscription.

18. Severability and entire agreement

If any provision of these Terms is held unenforceable, the rest remains in force. These Terms, together with the Privacy Policy and the Medical Disclaimer, are the entire agreement between you and us about Gimbal.

19. Contact

Questions about these Terms: contact@muzo.dev, subject line "Gimbal terms". Postal contact details are available on request and are filed with the App Store and Google Play as required for EU trader disclosure.

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