End User License & Terms of Service

Nanjing Xiayuyue Network Technology Co., Ltd.

Effective Date: June 2026 · Last Updated: October 2026

1. Software License Grant (EULA)

1.1 License Grant: Subject to these Terms, we grant you a personal, revocable, non-exclusive, non-transferable, and non-sublicensable limited license to install and run the App on Apple iOS devices (iPhone, iPad) that you own or control.

1.2 License Restrictions: You may not decompile, reverse engineer, disassemble, decrypt, or attempt to derive the source code of the App. All rights not expressly granted to you are reserved by the Developer.

2. Features, Subscription & Paid Services

2.1 Free Core Features: Basic AR length measurements, single polygon area calculation, on-screen ruler, and spirit level tools are available for free.

2.2 Pro Subscription Privileges: Advanced surveying capabilities (unlimited projects, AutoCAD DXF export, Bill of Materials BOM Excel generation, inspection report PDF, photo dimension callouts, watermark camera records, and BLE laser rangefinder calibration) require an active Pro subscription or lifetime purchase.

2.3 Membership Agreement Reference: Specific rules regarding billing cycles, free trials, renewal cancellation, and Apple Store refunds are governed by our dedicated Membership Agreement. In case of any conflict regarding subscription rights, the Membership Agreement shall prevail.

3. Engineering Measurement Disclaimer & Accuracy Limitations

3.1 Auxiliary Surveying Tool: The App utilizes consumer-grade mobile cameras, LiDAR sensors, and Apple ARKit spatial tracking algorithms. The App is strictly intended as an auxiliary estimation tool for preliminary site survey, interior layout drafting, material estimation, and visual evidence logging. It is NOT certified as a state-standardized legal metrology device.

3.2 Environmental Error Tolerance: Measurement accuracy depends on ambient lighting, texture sparsity (e.g., reflective glass, mirrors, plain featureless walls), user hand movement, and device sensor calibration. Physical tolerances and variances are inherent to optical AR technology and do not constitute a software defect.

3.3 Mandatory Physical Verification for Critical Tasks: For irreversible, high-cost, or structural engineering procedures—including but not limited to custom cabinetry fabrication, stone slab cutting, load-bearing modifications, structural window installation, and high-volume material procurement—YOU MUST MANUALLY VERIFY DIMENSIONS USING CALIBRATED PHYSICAL GAUGES (STANDARD STEEL TAPES OR METROLOGICAL LASER RANGEFINDERS). We assume no liability for material wastage, re-fabrication costs, or construction delays resulting from direct reliance on AR measurements without physical re-verification.

3.4 Irreversible Commercial Deliverables: Once you export AutoCAD (.dxf) vector schematics, BOM spreadsheets, or signed PDF inspection reports and deliver them to contractors or clients, the core commercial service is deemed fully delivered and consumed.

4. Local-First Architecture & User Data Responsibility

4.1 Local Sandbox Storage: We adhere to a strict Local-First data architecture. All your survey records, project hierarchies, watermark site photos, and exported CAD files reside exclusively on your device's local storage. We maintain no cloud database of your engineering data.

4.2 User Backup Responsibility: You are solely responsible for exporting your CAD/PDF files and backing up your iOS device via iCloud/Finder. Deleting the App or resetting your device will permanently erase local data, which cannot be retrieved by the Developer.

5. Intellectual Property

The App, including its visual designs, interactive UI, vector CAD rendering engine, branding, algorithms, and source code, is the proprietary property of Nanjing Xiayuyue Network Technology Co., Ltd. and is protected by copyright, trademark, and international intellectual property laws.

6. Limitation of Liability

6.1 As-Is Basis: The App is provided "as is" and "as available" without warranties of any kind, whether express or implied.

6.2 Indirect Damages Disclaimer: To the maximum extent permitted by applicable law, in no event shall the Developer be liable for any indirect, incidental, special, consequential, or punitive damages (including loss of profits, construction delays, or business interruption).

6.3 Cap on Liability: Our total cumulative liability arising out of or related to these Terms or the App shall not exceed the total amount actually paid by you for the App in the twelve (12) months preceding the incident giving rise to liability.

7. Governing Law & Dispute Resolution

These Terms shall be governed by and construed in accordance with the laws of the People's Republic of China. Any dispute arising out of or in connection with these Terms shall be settled through amicable negotiation; if unresolved, either party may file a lawsuit before the competent People's Court located in Nanjing, China.

8. Contact Information