PRIVACY POLICY

This Privacy Policy explains how engineer bolt and nut, installed on devices as bolt and nut and also described in the app as Fastener Spec, handles data.

The app is a technical reference app for fastener dimensions, including nuts and bolts. Fastener lookup data is bundled with the app and lookup behavior runs locally on your device.

Key points:

• Fastener dimension lookup runs locally on your device.
• App settings are saved locally with Android SharedPreferences.
• The app does not operate user accounts, an analytics server, or a remote lookup history database.
• The app uses Google Mobile Ads, which may collect and share data for advertising, analytics, and fraud prevention.

The app itself does not collect personal information such as:

• Name, email address, phone number, or account profile.
• Contact lists, calendar data, camera data, or microphone data.
• Precise GPS location.
• Lookup history transmitted to our server.

Local data stored by the app:

• Theme mode.
• Detail level, such as Min, Basic, or Max.
• Large text setting.
• Heavy Hex setting.
• Native ad display count and last shown time.

These settings are saved on your device with SharedPreferences and are removed according to Android app data behavior, such as when you clear app data or uninstall the app.

Fastener dimension data:

• ASME B18.2.2-related fastener data files are bundled with the app.
• Metric and unified nut and bolt lookups are processed on device.
• Selected size, standard, and detail level are not sent to our server.

Saved images:

• When you use Save, the app writes the generated spec image to your device.
• Saved image file names may include a timestamp to avoid duplicate names.
• On Android 10 and later, image saving uses MediaStore without storage permission.
• On Android 9 and earlier, Android may require WRITE_EXTERNAL_STORAGE permission.

When you use Copy, the selected spec text is placed on your device clipboard.

This app uses Google Mobile Ads to display advertisements. According to Google's Mobile Ads SDK disclosure, the SDK may automatically collect and share data for advertising, analytics, and fraud prevention.

Google Mobile Ads may process data such as:

• IP address, which may be used to estimate general location.
• User product interactions, such as ad impressions, taps, and video views.
• Diagnostic information, such as SDK performance and app launch information.
• Device and account identifiers, including Android Advertising ID and App Set ID where available.

This data is handled by Google and its advertising partners according to their own policies. Data collected by Google Mobile Ads is encrypted in transit according to Google's SDK disclosure.

This application declares the following permissions:

• INTERNET: Used to load advertisements.
• AD_ID: Used by Google Mobile Ads for advertising, measurement, and fraud prevention when available on the device.
• VIBRATE: Used for lightweight selection feedback inside the app.
• WRITE_EXTERNAL_STORAGE: Used only on Android 9 and earlier when saving images.

The app does not request camera, microphone, precise location, contacts, calendar, phone, or account permissions.

Because the app does not operate user accounts or a remote user database, there is no app account profile to access, export, or delete.

You can control local app data by:

• Changing settings inside the app.
• Clearing app data in Android system settings.
• Uninstalling the app.

You can control advertising identifiers through Android settings. Depending on your Android version, you may be able to reset or delete your Advertising ID, or turn off ad personalization.

The app is designed to keep app lookup behavior local:

• Fastener data files are read from the app package.
• App preferences are stored in Android SharedPreferences.
• Saved images are written to device storage only when you use Save.
• Advertising SDK network traffic is handled by Google Mobile Ads and is encrypted in transit according to Google's SDK disclosure.

This summary is intended to help users understand the same categories commonly used in Google Play Data Safety disclosures.

Collection

• App itself: Stores settings locally on the device only.
• Google Mobile Ads SDK: May collect IP address, user product interactions, diagnostics, and device/account identifiers.

Sharing

• App itself: Does not send lookup data or settings to our server.
• Google Mobile Ads SDK: May share data for advertising, analytics, and fraud prevention.

Purpose

• Local settings: Restore your app preferences.
• Advertising data: Deliver ads, measure ad performance, and prevent fraud.

User control

• You can clear app data or uninstall the app to remove local settings.
• You can reset or delete your Advertising ID in Android settings where supported.

The app may open external Google Play pages for related apps and uses Google Mobile Ads for advertising. The app also includes an in-app library notice screen for major third-party libraries and bundled font information.

Useful Google resources:

• Google Privacy Policy
• Google Ads Privacy
• Manage Google Ad Settings

Third-party services and websites are governed by their own privacy policies and terms.

The app is a technical reference app for fastener dimensions. The app itself does not ask users to create accounts or provide personal information.

Advertising services may process data as described in this policy. Parents or guardians can use Android device settings to manage the device's Advertising ID and ad personalization options where available.

When this Privacy Policy changes:

• Updated policy text may be provided through an app update.
• Material changes may be noted in the app or store listing where appropriate.

Your continued use of the app after an update means you are using the app under the updated policy.

If you have questions or concerns about this privacy policy or our practices, please contact us at:

Email: xonnetdev2@gmail.com

We will review inquiries as soon as reasonably possible.

This Privacy Policy takes effect from the time of app installation and use.

Last Updated: June 2026