Last updated: July 15, 2026 / Version 1.0
1. Application of These Terms
These Terms of Service ("Terms") set out the conditions for using "rVAS" (the "App"), a general-purpose research tool for recording Visual Analogue Scale (VAS) responses. Anyone who uses the App (the "User") shall do so only after agreeing to these Terms.
2. Nature of the App
The App is a general-purpose research tool that is not limited to any specific field. It is software that lets users (researchers) freely design experimental conditions, stimulus media, VAS items, presentation patterns, and subject-information forms, and use them to record and aggregate subjects' subjective ratings in VAS format.
The App is not a medical device. It is not designed for diagnosis, treatment, or any other medical purpose, and must not be used as a basis for medical decisions.
3. Responsibilities of the User (Researcher)
Users shall use the App in compliance with applicable laws, the regulations of their affiliated institution, and applicable research ethics guidelines.
A User who conducts research or experiments involving human subjects using the App is solely responsible for the following matters:
- Obtaining any research ethics review required by their institution or organization to conduct the research
- Explaining the research to subjects and obtaining their informed consent
- Lawfully collecting, storing, using, and disposing of subject information (including personal information such as name, age, and sex)
- Ensuring the legality and security of any sharing of experiment result data (e.g., XLSX export files) or project design data (e.g., .rvas files) with external parties
- Managing their device (e.g., protecting against loss or theft, keeping the OS and App updated, and maintaining backups)
The App stores subject information and other data only on the device, and is designed so that the developer cannot access it. Responsibility for managing this data therefore rests with the User (researcher), not the developer.
4. Prohibited Conduct
When using the App, Users shall not engage in any of the following:
- Acts that violate any law or public order and morals
- Collecting or using personal information without the subject's consent
- Using the App as a substitute for medical practice (diagnosis, treatment, etc.)
- Unauthorized reproduction, modification, or reverse engineering of the App's software (except where permitted by law)
- Acts that interfere with the normal operation of the App
5. Data and Intellectual Property
Project settings, subject information, experiment results, and other data created within the App are stored on the User's own device and are managed by the User. Rights to this data belong to the User.
Intellectual property rights relating to the App's software, design, name, and other elements belong to the developer (or other rightful owner).
6. Purchases and Payments (In-App Purchases)
The App may offer subscription (monthly or annual) or one-time (non-consumable) purchases. The following applies to such purchases:
- Payment processing is handled through Apple's StoreKit, and payment information such as credit card details is managed by Apple (or its payment processing partner). The developer does not retain or view this payment information.
- Pricing plans and the availability and duration of any free trial, as well as details of the purchase process, are governed by what is displayed on the relevant product page in the App Store.
- Cancellations and refunds are subject to Apple's policies and procedures (such as the App Store refund request process); the developer does not process refunds directly.
- Regardless of whether a purchase has been made, subject information, experiment results, and other data already stored on the device will not be deleted or made inaccessible for viewing or export.
- If there is any discrepancy between this Section and the terms displayed on the App Store, the terms displayed on the App Store and Apple's own terms of service (including the Apple Media Services Terms and Conditions) shall control.
7. No Warranty
The App is provided "as is." The developer makes no warranty, express or implied, that the App will be suitable for any particular research purpose, that VAS measurement values will be accurate, or that operation will be free of interruption or error.
Values recorded by the App (such as VAS measurement values) may be affected by factors including the device's display calibration. Users are responsible for verifying the validity of this data for research purposes.
In addition, the App is a tool intended to support research activities, and does not guarantee the results, conclusions, or academic validity of any research conducted using it.
8. Disclaimer
To the extent permitted by law, the developer shall not be liable for any damages (including, without limitation, data loss, delays to research, or lost opportunities) incurred by a User or any third party (including subjects) arising from use of, or inability to use, the App. This limitation does not apply where such damages result from the developer's willful misconduct or gross negligence.
9. Changes to or Discontinuation of the Service
The developer may change the content of the App or discontinue providing it, while making reasonable efforts to give Users advance notice. Because App data is stored only on the device, discontinuation of the service does not prevent Users from retaining, viewing, or exporting existing data on their device, although updates and support for the App may end.
10. Changes to These Terms
The developer may revise these Terms when deemed necessary. Revised Terms take effect once posted within the App or on this page.
11. Governing Law and Jurisdiction
These Terms shall be interpreted in accordance with the laws of Japan. Any dispute arising between a User and the developer in connection with the App shall be subject to the exclusive jurisdiction of the court having jurisdiction over the developer's location as the court of first instance.
12. Contact
If you have any questions about these Terms, please contact us at the address below.
Developer: Takuya Watanabe
Contact email: