Last updated: October 17, 2026
Zhiyong Zhang provides the WebPower Android and iOS apps and related WebPower services at no cost. This policy explains what information may be processed when you use the apps and service, why it is processed, and the choices available to you.
This policy applies to the WebPower Android and iOS apps and the WebPower services they connect to, including https://webpower.psychstat.org/.
Information you provide for an account. If you register or sign in, WebPower processes information you submit, which may include your username, password, email address, name, work or home address, and country. The apps send registration and sign-in information to WebPower over HTTPS so the service can create or authenticate your account. Neither app keeps your password as a saved app setting.
Calculator submissions and saved analyses. When you run a calculator, the app sends the values you enter—such as sample sizes, effect sizes, options, and any analysis note—to WebPower to perform the calculation and return its results. If you are signed in, the service may associate an analysis and its results with your account so you can view saved analyses later. Avoid entering personal or sensitive information in calculator fields or notes unless it is necessary for your analysis.
Registration CAPTCHA. Account registration uses Google reCAPTCHA to help prevent abuse. The CAPTCHA response is sent to WebPower for verification. The iOS app displays reCAPTCHA in a web view. Google may process technical and interaction information in connection with reCAPTCHA under its own policies.
Technical and session information. When an app connects to WebPower, WebPower and its hosting providers may receive standard connection information, such as your IP address, request date and time, and device, operating-system, or browser information. The Android app uses WebView cookies, and the iOS app uses iOS cookie storage, to maintain WebPower sessions and make authenticated requests. The iOS app uses WebKit only for the reCAPTCHA widget and to render isolated SVG result figures; it does not display WebPower website pages. Google reCAPTCHA may also use cookies or similar technologies during registration.
WebPower uses information described in this policy as needed to:
The Android and iOS apps do not include advertising or analytics SDKs. This does not describe any separate data practices of the WebPower website or of third-party services.
WebPower may provide information to service providers that help operate the service, such as website hosting providers, and to Google for reCAPTCHA verification. They process information as needed to provide those services and are subject to their applicable terms and privacy practices.
Google reCAPTCHA is provided by Google and may process information under Google’s Privacy Policy and Terms of Service.
The apps do not send account or calculator information to advertising networks for targeted advertising. WebPower may also disclose information when required by law or when reasonably necessary to protect the service, its users, or others.
WebPower session cookies are used to maintain sign-in and support authenticated features, including saved analyses. The Android app uses Android WebView cookies. The iOS app uses iOS cookie storage for WebPower requests. Signing out clears the WebPower session cookies used by the app; you will need to sign in again to use account features. Google reCAPTCHA may use its own cookies or similar technologies during registration. Blocking these technologies may prevent registration or other related features from working.
WebPower retains account information and saved analyses while they are needed to provide the service. You may request deletion of your WebPower account and associated files and information by emailing webpower@psychstat.org. Include enough information for WebPower to identify the account; WebPower may need to verify the request. WebPower will process deletion requests within a reasonable period, subject to information that must be retained for legal, security, or fraud-prevention reasons.
Technical records may be retained for as long as reasonably necessary to operate, secure, and troubleshoot the service, or as required by law.
Signing out clears the app’s locally stored WebPower session cookies; it does not delete your WebPower account or saved analyses. Use the deletion-request process above to request account and associated-data deletion.
The apps communicate with WebPower over HTTPS. WebPower uses reasonable safeguards intended to protect information it processes. No method of internet transmission or electronic storage can be guaranteed to be completely secure.
You can choose not to create an account. Account features, including saved analyses and calculators that require sign-in, will then be unavailable. You may sign out in either app to clear its locally stored WebPower session cookies.
For requests to access, correct, or delete information associated with a WebPower account, contact webpower@psychstat.org.
WebPower is not directed to children under 13, and WebPower does not knowingly collect personal information from children under 13. If you believe a child has provided personal information to WebPower, contact webpower@psychstat.org so the information can be reviewed and appropriate action taken.
The service may link to websites operated by others. Those sites have their own privacy policies and practices. WebPower is not responsible for the content or privacy practices of external sites.
WebPower may update this policy. The current version will be posted on this page with its updated date. Please review it periodically.
For questions or requests about this policy or information associated with a WebPower account, contact: