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Terms of Service

Effective date: 24 May 2026

1. Provider

These Terms of Service (“Terms”) govern your use of the Charles mobile application (“Charles”, “the App”) and all related services provided by:

ViaVia UG (haftungsbeschränkt) Marchgrabenplatz 4 80805 München, Germany

Commercial Register: Amtsgericht München, HRB 308987 Managing Director: Klemen Kocic Email: info@viavia.travel

By downloading, installing, or using the App, you agree to these Terms. If you do not agree, do not use the App.

2. Service Description

Charles is an AI-powered strength training application that generates personalised training plans based on your fitness assessment. The App provides:

  • Personalised training programme generation based on your assessment data
  • Periodised programming across accumulation and intensification phases
  • Workout tracking with exercise logging (sets, reps, weights)
  • Session feedback and programme adaptation
  • Exercise demonstration animations

3. Eligibility

You must be at least 13 years of age to use Charles. If you are between 13 and 17 years of age, you confirm that you have the consent of a parent or legal guardian to use the App. We reserve the right to request proof of age or parental consent at any time.

4. Account Registration

  • You must create an account to use Charles. Account creation is available via email, Apple Sign-In, or Google Sign-In.
  • You are responsible for maintaining the confidentiality and security of your account credentials.
  • You must provide accurate and complete information during registration and assessment.
  • One person may maintain only one account. Creating multiple accounts to abuse free trials or for any other purpose is prohibited.
  • You are responsible for all activities that occur under your account.
  • You must notify us promptly at info@viavia.travel if you become aware of any unauthorised use of your account.

5. Subscriptions and Payment

5.1 Free Trial

New users are eligible for a 7-day free trial of Charles Pro. The trial provides full access to all features. If you do not cancel before the trial period ends, your subscription will automatically begin and you will be charged.

5.2 Subscription Plans

Charles Pro is available at the following prices:

  • Monthly: EUR 9.99 per month
  • Annual: EUR 69.99 per year

Prices are inclusive of applicable VAT. Actual prices may vary by country and currency based on App Store or Play Store pricing.

5.3 Billing and Renewal

  • Payment is charged to your Apple ID or Google account at confirmation of purchase.
  • Subscriptions automatically renew at the end of each billing period unless cancelled at least 24 hours before the end of the current period.
  • Your account will be charged for renewal within 24 hours prior to the end of the current period at the rate of the selected plan.

5.4 Cancellation

  • You can cancel your subscription at any time through your device’s subscription settings:
    • iOS: Settings > [your name] > Subscriptions > Charles
    • Android: Google Play Store > Menu > Subscriptions > Charles
  • Cancellation takes effect at the end of the current billing period. You retain access to Charles Pro features until the end of the paid period.
  • Cancellation does not entitle you to a refund for the current billing period.

5.5 Pricing Changes

We may change subscription prices with at least 30 days’ advance notice. Price changes do not affect the current billing period. You will be notified of any price changes before they take effect, and continued use after the change constitutes acceptance of the new price. If you do not agree to the new price, you may cancel your subscription before the change takes effect.

6. Refund Policy

Refunds for in-app purchases and subscriptions are handled by the respective app store according to their refund policies:

  • Apple App Store: Request refunds at https://reportaproblem.apple.com
  • Google Play Store: Request refunds at https://support.google.com/googleplay/answer/2479637

We do not process refunds directly for store-billed purchases.

7. Right of Withdrawal (Widerrufsrecht)

7.1 Withdrawal Right

As a consumer in the European Union, you have the right to withdraw from the contract within 14 days without giving any reason. The withdrawal period begins on the day the contract is concluded.

To exercise your right of withdrawal, inform us by a clear statement (e.g., email to info@viavia.travel) of your decision to withdraw.

7.2 Consequences of Withdrawal

Upon withdrawal, we will refund all payments received from you without undue delay and no later than 14 days from the day we received your withdrawal notice. We will use the same means of payment you used for the original transaction.

7.3 Early Expiry of Withdrawal Right for Digital Content

For digital content not delivered on a physical medium: You expressly consent to us beginning contract performance before the withdrawal period expires, and you acknowledge that you lose your right of withdrawal once performance has begun (ss 356 Abs. 5 BGB).

We will provide you with confirmation of this consent on a durable medium (email) after contract conclusion.

7.4 Services

For digital services: The withdrawal right expires when the service has been fully performed, provided we began performance with your express prior consent and your acknowledgment that the withdrawal right expires upon full performance (ss 356 Abs. 4 BGB).

8. Health Disclaimer

IMPORTANT: Please read this section carefully.

  • Charles provides AI-generated training recommendations only. It is not a substitute for professional medical advice, diagnosis, or treatment.
  • Charles is not a medical device and is not intended to diagnose, treat, cure, or prevent any disease or medical condition.
  • You must consult a qualified physician before starting any exercise programme, especially if you have any pre-existing health conditions, injuries, physical limitations, or if you are pregnant.
  • The training plans generated by Charles are based on general strength training principles applied to the assessment data you provide. They do not account for medical conditions not disclosed during the assessment.
  • You use the training plans and exercise recommendations entirely at your own risk. ViaVia UG is not liable for any injuries, health complications, or damages of any kind resulting from following the programmes generated by Charles.
  • If you experience pain, dizziness, shortness of breath, or any other discomfort during exercise, stop immediately and consult a healthcare professional.
  • Charles does not provide nutritional advice, rehabilitation protocols, or physiotherapy guidance. For these needs, consult the appropriate qualified professional.

9. User Content and Data

9.1 Your Data

You retain all rights to the data you provide through the App, including your assessment responses, workout logs, and feedback. By using the App, you grant us a limited, non-exclusive, worldwide licence to process your data solely to provide the App’s functionality to you.

We do not claim ownership of your data. We do not sell your data to third parties. We do not use your data for advertising purposes.

9.2 Data Processing

Your assessment data and training history are processed by AI (Google Gemini API) to generate and refine your training plans. Only data necessary for plan generation is transmitted to the AI model. No personally identifiable information (such as your email address or name) is sent to the AI. For full details, see our Privacy Policy.

9.3 Data Deletion

You can delete your account and all associated data at any time through the Account section of the App. Upon deletion, all your personal data is permanently removed, subject to legal retention obligations as described in our Privacy Policy.

10. Intellectual Property

10.1 Our Content

The App, including its design, user interface, code, logos, training methodologies, exercise programming logic, brand elements, and all documentation, is owned by ViaVia UG and protected by copyright and other intellectual property laws. You may not copy, modify, distribute, decompile, reverse engineer, or create derivative works from any part of the App.

10.2 Exercise Content

Exercise demonstration animations and data used in Charles are licensed from third-party providers. These materials are provided for your personal, non-commercial use within the App only. You may not download, redistribute, or use these materials outside of the App.

10.3 Feedback

If you provide us with suggestions, ideas, or feedback about the App, you grant us a non-exclusive, royalty-free, worldwide licence to use, modify, and incorporate such feedback into the App without obligation to you.

11. Prohibited Use

You may not:

  • Use the App for any unlawful purpose or in violation of any applicable law
  • Attempt to reverse engineer, decompile, disassemble, or otherwise attempt to derive the source code of the App
  • Use automated systems, bots, or scrapers to access the App or extract data
  • Interfere with, disrupt, or overburden the App’s servers or infrastructure
  • Create multiple accounts to abuse free trials or for any other deceptive purpose
  • Share, transfer, or sell your account to another person
  • Impersonate another person or entity
  • Use the App to distribute malware, spam, or other harmful content
  • Attempt to gain unauthorised access to other users’ accounts or our systems
  • Remove, alter, or obscure any copyright notices or other proprietary markings
  • Use the App’s content (including exercise animations) outside of the App
  • Commercially exploit any part of the App without our written permission

12. Limitation of Liability

12.1 Unlimited Liability

We are liable without limitation for:

  • Intentional misconduct (Vorsatz)
  • Gross negligence (grobe Fahrlassigkeit)
  • Injury to life, body, or health
  • Claims under the Product Liability Act (Produkthaftungsgesetz)
  • Guarantees expressly assumed by us

12.2 Limited Liability

For slight negligence (leichte Fahrlassigkeit) in the breach of material contractual obligations (Kardinalpflichten), our liability is limited to the foreseeable, typically occurring damages. Material contractual obligations are those whose fulfilment is essential for the proper execution of the contract and on whose compliance the contractual partner may regularly rely.

12.3 Exclusion

Beyond the cases described in sections 12.1 and 12.2, liability for slight negligence is excluded.

This limitation of liability also applies to our legal representatives, employees, and vicarious agents (Erfullungsgehilfen).

13. Indemnification

To the extent permitted by applicable law, you agree to indemnify and hold harmless ViaVia UG, its directors, employees, and agents from and against any claims, damages, losses, liabilities, costs, and expenses (including reasonable legal fees) arising out of or related to:

  • Your breach of these Terms
  • Your misuse of the App
  • Your violation of any applicable law or third-party rights
  • Any injury or health issue arising from your use of training plans generated by the App (to the extent not caused by our intentional or grossly negligent conduct)

This indemnification obligation does not apply to the extent that you are not responsible for the relevant breach or violation.

14. Availability and Maintenance

We strive to maintain the App’s availability but do not guarantee uninterrupted access. We may temporarily suspend the App for maintenance, updates, security patches, or circumstances beyond our control. We will provide advance notice where reasonably possible.

We reserve the right to modify, update, or discontinue features of the App at any time. Material changes to core functionality will be communicated with reasonable notice.

15. Termination

  • You may terminate your account at any time by deleting it through the Account section of the App, or by contacting info@viavia.travel.
  • We may suspend or terminate your account if you violate these Terms, with reasonable notice where possible.
  • Upon termination, your right to use the App ceases immediately. You may request a copy of your data before termination (Art. 20 GDPR).
  • Termination does not affect any rights or obligations that have accrued prior to termination, including any outstanding payment obligations.

16. Governing Law and Jurisdiction

These Terms are governed by the laws of the Federal Republic of Germany, excluding the UN Convention on Contracts for the International Sale of Goods (CISG).

For consumers: Mandatory consumer protection provisions of your country of residence apply where they provide greater protection. You may bring proceedings in the courts at your place of residence or before the courts of Munich.

For businesses: The exclusive place of jurisdiction is Munich, Germany (AG München for claims up to EUR 5,000; LG München I for claims above EUR 5,000).

17. Online Dispute Resolution

The European Commission provides an Online Dispute Resolution (ODR) platform at https://ec.europa.eu/consumers/odr. We are neither obliged nor willing to participate in dispute resolution proceedings before a consumer arbitration board.

18. Changes to These Terms

We may modify these Terms with at least 30 days’ advance notice via email or in-app notification. If you do not agree to the modified Terms, you may terminate your account before they take effect. Continued use of the App after the effective date constitutes acceptance of the modified Terms.

19. Severability

If any provision of these Terms is found to be invalid or unenforceable by a court of competent jurisdiction, the remaining provisions remain in full force and effect. The invalid provision shall be replaced by a valid provision that most closely reflects its economic intent.

20. Entire Agreement

These Terms, together with our Privacy Policy and Impressum, constitute the entire agreement between you and ViaVia UG regarding your use of the App and supersede all prior agreements and understandings.

21. Contact

For questions about these Terms:

ViaVia UG (haftungsbeschränkt) Marchgrabenplatz 4 80805 München, Germany Email: info@viavia.travel