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Terms of Use

CaffCurve — Caffeine & Sleep Tracker
JappJ Studio, operated by Julian Junker

Effective date: September 30, 2026
Last updated: October 17, 2026

1. Acceptance of Terms

By downloading, installing, or using CaffCurve (“the App”), you agree to be bound by these Terms of Use (“Terms”). If you do not agree to these Terms, do not use the App.

These Terms form a legally binding agreement between you and JappJ Studio, a sole proprietorship of Julian Junker, Switzerland (“we,” “us,” or “our”). Apple’s Standard End User License Agreement, available at apple.com/legal/internet-services/itunes/dev/stdeula, also applies to your use of the App. Where these Terms and Apple’s Standard EULA conflict on a matter specific to the relationship between you and Apple (Section 19 below), Apple’s terms prevail; for everything else governing your relationship with us, these Terms prevail.

2. Eligibility

The App is rated 16+ on the App Store, and you must be at least 16 years old to use it. The App does not verify your age itself. If you are a minor (under the age of majority where you live), you may use the App only with the consent of a parent or legal guardian where local law requires it, and that parent or guardian agrees to be bound by these Terms on your behalf. You must otherwise have the legal capacity to enter into a binding agreement in your place of residence. If you are a parent or guardian and believe a child under 16 has used the App, please contact us.

3. License

Subject to your compliance with these Terms and Apple’s Usage Rules, we grant you a limited, non-exclusive, non-transferable, revocable license to download and use the App on Apple-branded devices that you own or control, solely for your personal, non-commercial purposes.

You may not:

Copy, modify, or create derivative works of the App or its content
Reverse engineer, decompile, or disassemble the App
Rent, lease, lend, sell, or sublicense the App
Remove or alter any proprietary notices or labels on the App
Use the App for any unlawful purpose or in violation of these Terms

4. In-App Purchases and Subscriptions

4.1 Subscription Summary

CaffCurve offers an auto-renewing subscription (“Premium”) that automatically renews until you cancel it.
Payment is charged to your Apple ID account at confirmation of purchase, and renewal is charged within 24 hours before the end of your current billing period.
To cancel: go to Settings → [your name] → Subscriptions on your device, or see Apple’s subscription management guide. Cancel at least 24 hours before the current period ends to avoid being charged for the next one.
If a free trial is offered, it converts automatically into a paid subscription unless you cancel at least 24 hours before the trial ends.
We do not issue refunds directly — all refund requests go through Apple (Section 4.4).

4.2 Plans, Pricing, and Free Trials

We do not state fixed prices or a fixed free-trial length in these Terms. The exact subscription plans available, their price and billing period, and any free-trial length, are shown in the App and on its App Store product page before you confirm a purchase, and those are the terms that apply to you. Prices are displayed in your local currency as determined by the App Store and may vary by region.

A free trial, where offered, is available once per Apple ID. Reinstalling the App does not reset trial eligibility.
Any unused portion of a free trial is forfeited if you purchase a subscription before the trial ends.
If you cancel before the trial ends, you will not be charged.

4.3 Billing and Renewal

Payment is charged to your Apple ID account at confirmation of purchase.
Subscriptions automatically renew unless auto-renewal is turned off at least 24 hours before the end of the current subscription period.
Your account is charged for renewal within 24 hours prior to the end of the current period.
You may manage your subscription and turn off auto-renewal at any time in your Apple ID account settings.

4.4 Cancellation and Refunds

Cancellations take effect at the end of the current billing period; you keep access until then. We do not provide refunds for partial subscription periods ourselves — all refund requests must be submitted directly to Apple via reportaproblem.apple.com. We have no control over, and no ability to override, Apple’s refund decisions.

4.5 EU/UK Right of Withdrawal

If you are a consumer in the EU or UK, you may ordinarily have a statutory right to withdraw from a purchase within 14 days. Because Apple is the merchant of record for all purchases made through the App, that right — and any exception to it for digital content you’ve started consuming with your consent — is administered by Apple as part of your purchase, not by us. Nothing in these Terms limits or waives any withdrawal or cancellation right that mandatory law grants you.

4.6 Price Changes

We reserve the right to change subscription prices. Price changes are communicated and, where required by Apple’s policies or applicable law, consented to through Apple’s own subscription price-change process — not by us directly. We do not promise that your price will stay fixed at your current plan’s price.

5. Important Health and Medical Disclaimer

CaffCurve is a personal wellness tool, not a medical device, and has not been evaluated by the FDA, Swissmedic, or any equivalent regulator.

The caffeine tracking, bedtime projection, and related features of the App are provided for general wellness and informational purposes only.
The caffeine half-life calculations and bedtime projections are estimates based on generalised, population-average pharmacokinetic data and do not account for your individual physiology, health conditions, medications, or other factors that affect caffeine metabolism. Your actual results will vary.
Nothing in the App constitutes medical advice, diagnosis, or treatment, and the App is not a substitute for professional medical advice.
Do not disregard professional medical advice, and do not delay seeking it, because of anything you read or experience in the App.
Do not use the App to make decisions about driving, operating machinery, or any other safety-critical activity. If you are experiencing a medical emergency, contact your local emergency services immediately — do not rely on the App.
If you have a medical condition, are pregnant or breastfeeding, are taking medication, or have any concern about your caffeine intake, consult a qualified healthcare professional before changing your diet or lifestyle based on anything in the App.
Excessive caffeine consumption can be harmful. The App’s suggested limits are general wellness guidelines, not medically prescribed thresholds.

By using the App, you acknowledge and accept these limitations.

6. User Data and Content

All data you enter into the App (caffeine logs, drink preferences, sleep settings, badges) is stored locally on your device using Apple’s SwiftData framework. We do not collect, access, or transmit this data to our servers. A separate, limited stream of anonymous subscription analytics is sent to RevenueCat, as described in our Privacy Policy — it contains no caffeine, sleep, or health data.

Optional iCloud Sync, when enabled, synchronises your data across your Apple devices using your own iCloud account, governed by Apple’s iCloud Terms of Service.

You are solely responsible for any data you enter into the App and for maintaining its accuracy.

7. Intellectual Property

The App, including its design, code, graphics, text, logos, badges, and all other content, is owned by JappJ Studio and is protected by Swiss and international intellectual property laws. All rights not expressly granted in these Terms are reserved.

The name “CaffCurve,” the JappJ Studio name, and associated logos are trademarks of JappJ Studio. You may not use these marks without our prior written permission.

8. Prohibited Uses

You agree not to use the App:

For any purpose that is unlawful or prohibited by these Terms
To attempt to gain unauthorised access to any part of the App or its related systems
To interfere with or disrupt the integrity of the App
To impersonate any person or entity
In any way that could damage, disable, or impair the App

9. Disclaimer of Warranties

THE APP IS PROVIDED “AS IS” AND “AS AVAILABLE,” WITHOUT WARRANTIES OF ANY KIND, EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, ACCURACY, OR NON-INFRINGEMENT.

We do not warrant that the App will meet your requirements or expectations, that it will be uninterrupted, timely, secure, or error-free, that any errors will be corrected, or that results obtained from using the App will be accurate or reliable.

Some jurisdictions do not allow the exclusion of certain warranties, so some of the above exclusions may not apply to you, and you may have additional rights that vary by jurisdiction. Nothing in this section limits any warranty obligation Apple has agreed to bear under its own terms (see Section 19.4).

10. Limitation of Liability

TO THE MAXIMUM EXTENT PERMITTED BY APPLICABLE LAW, JAPPJ STUDIO AND JULIAN JUNKER SHALL NOT BE LIABLE FOR ANY INDIRECT, INCIDENTAL, SPECIAL, CONSEQUENTIAL, OR PUNITIVE DAMAGES, INCLUDING WITHOUT LIMITATION LOSS OF DATA, LOSS OF PROFITS, OR PERSONAL INJURY, ARISING OUT OF OR IN CONNECTION WITH YOUR USE OF OR INABILITY TO USE THE APP, EVEN IF WE HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.

Our total liability to you for any claim arising from these Terms or your use of the App will not exceed the greater of (a) the amount you paid for the App or its subscription in the twelve (12) months preceding the claim, or (b) USD/CHF 50.

This limitation does not apply to liability that cannot be excluded or limited under mandatory law — including, without limitation, liability for gross negligence or intentional misconduct under Swiss Code of Obligations Article 100, liability that EU/UK consumer protection law does not allow to be excluded, and liability for death or personal injury where the law does not allow it to be limited. Some jurisdictions do not allow the exclusion or limitation of certain damages, so some of the above limitations may not apply to you.

11. Indemnification

You agree to indemnify, defend, and hold harmless JappJ Studio and Julian Junker from any claims, liabilities, damages, losses, costs, or expenses (including reasonable legal fees) arising from your use of the App, your violation of these Terms, or your violation of any rights of a third party.

12. Third-Party Services

The App uses the following third-party services:

Apple App Store / StoreKit — for payment processing and subscription management. Apple’s Privacy Policy and Terms of Service apply to transactions processed through the App Store.
Apple iCloud (optional, when enabled) — for data synchronisation across your devices. Apple’s iCloud Terms of Service apply.
RevenueCat, Inc. — for anonymous subscription analytics, in observer mode only. See our Privacy Policy for details of what is shared.

We are not responsible for the privacy practices or content of any third-party services.

13. Updates and Changes to the App

We reserve the right to modify, update, suspend, or discontinue the App or any part of it at any time, with or without notice. We are not liable to you or any third party for any modification, suspension, or discontinuation.

14. Changes to These Terms

We may update these Terms from time to time. We will notify you of changes by updating the “Last updated” date at the top of this page. For material changes that meaningfully reduce your rights or increase your obligations, we will also give you advance notice — via in-app notification where practicable — before the change takes effect, consistent with fair-dealing expectations under EU/UK and Swiss consumer law. Your continued use of the App after a change takes effect constitutes your acceptance of it. If you do not agree, you must stop using the App.

15. Assignment

We may assign or transfer these Terms, in whole or in part, without your consent — for example if JappJ Studio or the App is sold, merged, or otherwise transferred to another party. You may not assign or transfer your rights or obligations under these Terms to anyone else without our prior written consent.

16. Governing Law and Jurisdiction

These Terms are governed by and construed in accordance with the laws of Switzerland, excluding the United Nations Convention on Contracts for the International Sale of Goods (CISG) and Switzerland’s conflict-of-laws rules. Any dispute arising under or in connection with these Terms is subject to the exclusive jurisdiction of the courts of Biel/Bienne, Canton of Bern, Switzerland.

If you are a consumer resident in the EU, UK, or elsewhere, nothing in this section deprives you of the protection of the mandatory consumer-protection laws of your country of residence, including your right, where the law grants it, to bring proceedings in the courts of that country.

We do not require you to arbitrate disputes, and we do not ask you to waive your right to participate in a class action.

17. Severability

If any provision of these Terms is found to be invalid or unenforceable, that provision will be limited or eliminated to the minimum extent necessary, and the remaining provisions will remain in full force and effect.

18. No Waiver

Our failure to enforce any right or provision of these Terms is not a waiver of that right or provision.

19. Apple’s Minimum Terms

Because the App is distributed through the Apple App Store, the following terms — required by Apple’s Instructions for Minimum Terms of Developer’s End-User License Agreement — apply in addition to everything above:

This agreement is between you and JappJ Studio only, not Apple, and Apple is not responsible for the App or its content.
Scope of license: your license to use the App is limited to a non-transferable license to use it on any Apple-branded product that you own or control, as permitted by the Usage Rules in Apple’s App Store Terms of Service.
Maintenance and support for the App are our responsibility, not Apple’s, to the extent required by these Terms. Apple has no obligation to furnish any maintenance or support for the App.
Warranty: in the event of any failure of the App to conform to any applicable warranty, you may notify Apple, and Apple will refund the purchase price for the App to you (if any); to the maximum extent permitted by applicable law, Apple has no other warranty obligation with respect to the App, and any other claims, losses, liabilities, damages, costs, or expenses attributable to any failure to conform to any warranty are our sole responsibility.
Product claims: we, not Apple, are responsible for addressing any claims by you or any third party relating to the App or your possession and/or use of it, including: (a) product liability claims; (b) any claim that the App fails to conform to any applicable legal or regulatory requirement; and (c) claims arising under consumer protection, privacy, or similar legislation.
Intellectual property: in the event of any third-party claim that the App, or your possession and use of it, infringes that third party’s intellectual property rights, we, not Apple, are responsible for the investigation, defense, settlement, and discharge of any such claim.
Legal compliance: you represent and warrant that you are not located in a country subject to a US government embargo, or that has been designated by the US government as a “terrorist supporting” country, and that you are not listed on any US government list of prohibited or restricted parties.
Developer name and contact information: JappJ Studio, operated by Julian Junker, Switzerland — [email protected].
Third-party terms of agreement: you must comply with applicable third-party terms when using the App — for example, if you use a VoIP feature, you must not be in breach of your wireless data service agreement. (The App does not currently use VoIP.)
Third-party beneficiary: Apple and its subsidiaries are third-party beneficiaries of these Terms, and, upon your acceptance, Apple has the right (and will be deemed to have accepted the right) to enforce these Terms against you as a third-party beneficiary.

20. Entire Agreement

These Terms, together with our Privacy Policy and Apple’s Standard EULA, constitute the entire agreement between you and JappJ Studio regarding your use of the App and supersede all prior agreements and understandings.

21. Governing Language

These Terms are drafted in English. The English version is authoritative; any translation is provided for convenience only.

22. Contact

If you have questions about these Terms, please contact us:

JappJ Studio
A sole proprietorship of Julian Junker
Aarbergstrasse 46
2503 Biel/Bienne
Switzerland

Email: [email protected]
Website: jappjstudio.app