Rollmetry Permissions & Components

App: Rollmetry
Developer: HEBEI SNDAS SURVEY AND DRAW CO.,LTD.
Last Updated: November 5, 2026

Rollmetry works with compatible Bluetooth measuring wheels and uses Bluetooth communication, motion sensors, local storage, image selection, and file export to provide measurement functions. This page describes the principal permissions, system capabilities, and software components used by the current version.

The current version does not require an account or integrate advertising, analytics, user-tracking, or automatic crash-reporting SDKs. It does not provide an App-operated cloud synchronization service. Measurement data is processed and stored locally and is not automatically uploaded to our servers through the App.

Permission prompts depend on the operating-system version, device, and feature. Declaring a permission does not mean that the App requests it on every platform or during every use.

Android

• Bluetooth Scan on Android 12 and later: Accesses nearby Bluetooth advertisements, names, and system-provided device identifiers to discover compatible measuring wheels. Scan results are not used to infer your physical location.
• Bluetooth Connect on Android 12 and later: Connects to measuring wheels, reads connection status, and exchanges measurement and control data.
• Legacy Bluetooth permissions on Android 11 and earlier: Support Bluetooth discovery, connection, and communication on older systems.
• Location permission on Android 11 and earlier: Meets older operating systems’ authorization requirements for Bluetooth Low Energy scanning. The App does not obtain geographical coordinates through location services or use this permission for location tracking.
• Accelerometer and gyroscope: Support local heading, device orientation, calibration, and measurement calculations. These sensors generally do not require runtime authorization.
• Image selection: Reads background images you select through system or platform interfaces, without automatically browsing your entire photo library.
• File saving: Saves exports to your chosen destination through system interfaces. If system saving is unavailable, files may be saved in an available local App export directory.

The current Android version disables system application backup and uses backup and data-extraction rules to exclude App data from system cloud backups and system device transfers. Existing backups and independent manufacturer tools are controlled by the relevant systems or services.

iOS

• Bluetooth: Discovers and connects to compatible measuring wheels and exchanges measurement and control data. Bluetooth scanning does not request location permission.
• Motion sensors: System motion interfaces provide accelerometer and gyroscope readings for local heading, device orientation, and calibration calculations. Access is subject to system authorization and device capabilities.
• Image selection: Reads background images you choose. Photo-library authorization prompts depend on the operating-system version and selection method. The system photo picker does not necessarily require full photo-library authorization.
• File saving: The current export function uses the system file-saving interface to choose a destination. Ordinary file export does not require full photo-library access.

Bluetooth identifiers are supplied by iOS and should not be treated as the measuring wheel’s hardware MAC address. Inclusion of local App data in system backups or device transfers depends on system rules and your settings.

HarmonyOS

• Bluetooth: Supports measuring-wheel discovery, connection, and measurement and control data exchange.
• Accelerometer and gyroscope: Support local heading, device orientation, and measurement calculations.
• Approximate location declaration: The current version declares approximate location permission for Bluetooth compatibility. However, the current Bluetooth flow does not actively request this permission or read geographical location through location services.
• Images and files: Platform capabilities process background images and saving destinations you select.

Software Components

• flutter_blue_plus: Bluetooth Low Energy discovery, connection, and communication, including advertisements, device identifiers, connection status, and measuring-wheel data.
• Native motion sensor interfaces and sensors_plus: Platform-specific access to accelerometer and gyroscope readings for local heading, orientation, calibration, and measurement calculations.
• permission_handler: Permission-status checks and system permission requests.
• sqflite: Local database storage and retrieval of measurement records, Bluetooth connection records, and related information.
• shared_preferences: Local storage of language, display options, measurement settings, and calibration parameters.
• image_picker: Platform image selection for images you choose.
• path_provider and local file interfaces: Application-directory access and management of background images, local files, and temporary export files.
• File-generation components and system saving interfaces: Local generation and user-initiated saving of exports such as PNG, PDF, XLSX, and DXF.
• url_launcher: Opening privacy policies, support pages, and related links through system browsers or external applications.
• package_info_plus: Reading information about this App, such as its version, for display.
• audioplayers: Playback of bundled App notification sounds.
• wakelock_plus: Controlling screen wakefulness during relevant usage scenarios.

This list describes principal components and their functions; it is not a list of recipients to whom data is sent. Using these components does not itself mean that information is uploaded to their authors.

Local Processing and External Access

The current version does not automatically upload measurement records, Bluetooth connection records, sensor readings, or background images through the App to us or to advertising, analytics, tracking, or crash-reporting services.

Opening a webpage connects the system browser or external application to the relevant website. Selecting a cloud drive as a file destination may cause that service to upload or synchronize the file. Sending a support email allows the relevant email services and us to process its contents. These actions are separate from local measurement processing and depend on your choices and the relevant services.

The App writes relevant text to the system clipboard only when you choose an action such as copying a link.

Managing Permissions and Deleting Data

You can manage permissions that your operating system allows you to change in device settings. Denying or revoking a permission may prevent the corresponding feature from working.

Measurement records can be deleted through available App functions. Other local data can be managed through relevant App functions, system App-data controls, or uninstallation. Exported files and existing backups must be managed separately.

For complete information about retention, deletion, system backups, and external services, see the Rollmetry Privacy Policy.

For assistance, visit App Support or email service@sndas.com.

Developer / Operator:
HEBEI SNDAS SURVEY AND DRAW CO.,LTD.
河北圣达斯测绘工具有限公司