This Privacy Policy describes how the STL Viewer application (hereinafter - the Application, we) handles your information. STL Viewer is a viewer for STL 3D models that lets you open, visualize, measure, and export your 3D files. The Application is designed to keep your files on your device: we do not require an account, we do not operate our own servers, and we do not sell your data. The free version of the Application shows ads; a subscription removes them and unlocks pro features.
1.1. The 3D models you open, your list of recently opened files, your measurements, viewer settings (such as render mode, model color, and measurement units), and your preferences are stored locally on your device. This data is not uploaded to our servers and is not accessible to us.
1.2. Deleting the Application from your device deletes this local data, including your recently opened files list and settings.
2.1. The Application uses your device's file access and document picker so you can open STL files from your Files app or other apps. The Application reads only the files you choose to open; it does not scan your file storage in the background.
2.2. Exports (for example OBJ, DAE, or DXF conversions and screenshots of the 3D view) are created only when you explicitly request them, and the resulting file is handed to the destination you choose (for example, the iOS share sheet). We never receive a copy of your files, exports, or screenshots.
3.1. The Application generates a random, anonymous identifier on your device. It is not derived from your name, email address, phone number, or any other personal information — we never collect those. The identifier is used solely to manage your trial period and the status of your subscription.
3.2. Purchases and subscriptions are processed by Apple through the App Store and managed with RevenueCat, a subscription management service. We receive only anonymous purchase information (such as the product purchased and the subscription status) — never your payment details. RevenueCat processes this data according to its own privacy policy.
3.3. Because it is the App Store's responsibility to resolve refund issues, we may share anonymous information about your use of the Application with Apple Inc. in connection with refund requests.
4.1. The free version of the Application displays banner ads and rewarded video ads served by Google AdMob. Rewarded ads can temporarily unlock pro features. AdMob may use a device advertising identifier (such as Apple's IDFA) and information about the ads you see to deliver and measure ads.
4.2. On iOS, before any tracking we ask for your permission through the system App Tracking Transparency prompt. If you decline, ads still appear but are non-personalized. Subscribing removes ads entirely.
4.3. Google processes this data according to its own privacy policy.
5.1. To manage the trial period and time upgrade offers, the Application records anonymous usage counts — such as the number of sessions, how many files you have opened, and how often you use individual tools — together with your trial phase. These counts are stored on your device and attached to your anonymous RevenueCat identifier. They contain no model details, file names, or measurement values.
7.1. Your models and settings live only on your device and are retained until you delete them or remove the Application.
7.2. Records associated with your anonymous identifier (trial state and subscription status, held by RevenueCat) are retained only as long as needed to provide the service.
8.1. The Application is not directed to children under the age of 13 (or the equivalent minimum age in your jurisdiction), and we do not knowingly collect personal information from children.
9.1. All communication between the Application and third-party services (ads and subscription management) uses encrypted connections (HTTPS/TLS). Your local data is protected by your device's operating system security, including device encryption when enabled.
10.1. We may update this Privacy Policy from time to time. The current version is posted on this page, and the date of the latest revision is indicated at the top. Continued use of the Application after changes are posted constitutes acceptance of the updated Policy.
11.1. If you have questions about this Privacy Policy or how your data is handled, please contact us through the Apple App Store from which you downloaded the Application: use the App Support link on the Application's product page, or the Report a Problem feature in your App Store account. Refund requests are handled directly by the App Store.
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