1. Who is responsible
Ruler & Caliper (the “App”) and rulercaliper.app (the “Website”) are published by Yurii Koshkin in Spain. Privacy questions and data requests can be sent to support@rulercaliper.app.
2. What the App does not send to us
The App does not require an account and does not send your measurements, marker or jaw positions, calibration values, prices, transaction identifiers, support messages, or contact details through analytics. It contains no advertising, attribution, session replay, remote configuration, or third-party crash-reporting SDK.
The App does not request access to the camera, microphone, photos, contacts, or location. A bank or ID card is used only as a physical size reference; it is not scanned, photographed, or read.
3. Information stored locally on your iPhone
The App stores limited information on your device so it can work across launches:
- onboarding completion and your preferred unit;
- calibration factor and date;
- display dimensions, display scale, and iPhone hardware model identifier;
- free-measurement status and pending-purchase status; and
- a verified lifetime-entitlement record containing the product identifier, original Apple transaction identifier, and verification date.
Measurements and marker positions are calculated in memory and are not saved as a measurement history. Local information remains on the device until you reset it where the App provides that option or remove the App’s data, subject to backups and device services controlled by Apple.
4. Privacy-conscious product analytics
The App uses TelemetryDeck, provided by TelemetryDeck GmbH in Germany, to understand aggregate product use and improve the onboarding, calibration, measurement, and purchase experience. TelemetryDeck receives a hashed installation-scoped identifier, a session identifier, a rounded timestamp, and technical context such as App version, iPhone model, iOS version, language, region, time zone, display information, and accessibility preferences.
The App sends only closed product events and categorical results, such as onboarding progress, whether calibration succeeded, the selected ruler or caliper mode and unit, completion of the free measurement, paywall and offer states, and whether a purchase or restore attempt succeeded, was cancelled, remained pending, or failed. It does not send measured values, screen coordinates, calibration factors, product prices, currency, transaction identifiers, free-form error text, or anything you type.
We use these signals only for product analytics. They are not linked by us to your identity, are not used for advertising or cross-app tracking, and are not sold. TelemetryDeck says it does not store IP addresses and hashes identifiers before they reach its service. Learn more in the TelemetryDeck Privacy Policy and Privacy FAQ.
5. App Store purchases
Product information, purchases, entitlement verification, and purchase restoration are processed with Apple StoreKit. Apple may process Apple Account, payment, transaction, diagnostic, and device information under its own Privacy Policy. The publisher does not receive your payment-card details.
6. Support email
If you contact support, we receive the email address, message, and any attachments you choose to send. We use them to answer the request, diagnose the issue, prevent abuse, and meet applicable legal obligations. Do not send payment-card details, passwords, Apple Account credentials, or photographs of identification or bank cards.
Support correspondence is kept only as long as reasonably necessary to resolve the request and maintain an appropriate support record, unless a longer period is required by law. You may ask us to delete eligible correspondence at any time.
7. Website delivery data
The Website is delivered through OpenAI Sites on Cloudflare infrastructure. When you request a page, those infrastructure providers may process technical request and security information such as IP address, browser or user-agent information, requested URL, timestamp, and diagnostic or abuse-prevention data to deliver and protect the Website.
We do not add advertising trackers, analytics trackers, or marketing cookies to the Website. Infrastructure providers control their own security and operational retention practices. See the OpenAI Privacy Policy and Cloudflare Privacy Policy for more information.
8. Legal bases and purposes
Where the GDPR or similar law applies, support data is processed to respond to your request and provide the service, to comply with legal obligations, and for legitimate interests such as service security and abuse prevention. App-local data is processed on your device at your direction to provide the App’s functions. The limited TelemetryDeck signals are processed for our legitimate interest in understanding and improving the App with a proportionate, privacy-conscious analytics service.
9. International processing and security
Apple, TelemetryDeck, and the Website infrastructure providers may process information outside your country, subject to their safeguards and policies. TelemetryDeck states that its analytics infrastructure is hosted in Germany and the Netherlands. We use reasonable measures appropriate to the limited information we handle, but no electronic transmission or storage method can be guaranteed completely secure.
10. Your rights
Depending on applicable law, you may request access, correction, deletion, restriction, or objection regarding personal information we hold through support or Website operations. Contact support@rulercaliper.app. You may also lodge a complaint with the competent data-protection authority. Apple controls App Store transaction records and its own data.
11. Changes to this policy
We may update this policy when the App, Website, providers, or legal requirements change. The effective date at the top identifies the current version. Material changes will be presented through an appropriate notice where required.