Function Visualizer 隐私政策 Privacy Policy
Function Visualizer 是一款完全离线运行的数学函数可视化工具。我们不收集、不存储、不传输您的任何个人数据：应用不发起网络请求、不集成任何第三方统计或广告 SDK、不含账号系统与云同步，所有函数表达式、绘图设置与历史记录仅保存在您自己的设备上。您可以放心地按「不收集任何数据（Data Not Collected）」理解本应用的隐私实践。
Function Visualizer is a fully offline mathematical function visualizer. We do not collect, store, or transmit any personal data: the app makes no network requests, bundles no third-party analytics or advertising SDKs, and includes no account system or cloud sync. All expressions, plot settings, and history remain on your own device.
一、政策概览
本隐私政策说明 Function Visualizer（以下简称"本应用"）在 iOS、iPadOS 与 macOS 平台上如何处理与您有关的信息。本应用由独立开发者提供，通过 App Store 以付费下载方式分发（定价 4.99 美元，支持 iOS 与 macOS 通用购买）。
本应用的核心功能是在您的设备本地完成数学函数（含显式函数、隐式方程与三维曲面）的解析、计算与绘制。所有计算过程均在本机 CPU/GPU 上完成，不依赖任何远程服务器。
- 不收集任何数据：我们不收集、不使用、不出售任何可识别个人身份的信息，也不收集设备标识符、位置、通讯录、健康、浏览记录等任何类别数据。
- 不追踪、不做广告：本应用不包含广告 SDK、归因 SDK 或跨应用/跨网站追踪能力，未声明并使用 App Tracking Transparency（ATT）相关键值。
- 不联网上传：应用内不存在网络请求代码；macOS 版本在系统沙盒（App Sandbox）中运行且未申请网络客户端权限，操作系统层面即可阻断任何外联。
二、我们明确不收集的数据类型
为便于比对 App Store 的隐私问卷（App Privacy Details），下表说明本应用对各类常见数据类别的处理方式。全部类别均为"不收集"。
| 数据类别 | 是否收集 | 应用内的实际情况 | 是否与身份关联 |
|---|---|---|---|
| 联系信息（姓名、邮箱、电话） | 否 | 无账号注册、无登录、无表单提交 | 不适用 |
| 位置信息 | 否 | 未申请定位权限，代码中无定位相关 API | 不适用 |
| 标识符（IDFA / IDFV / 设备指纹） | 否 | 未调用广告标识符，未接入任何归因或统计服务 | 不适用 |
| 使用数据与诊断（崩溃日志、行为统计） | 否 | 无第三方统计 SDK；仅使用系统本地的 UserDefaults 保存设置 | 不适用 |
| 用户内容（函数表达式、绘图、导出图片） | 否 | 仅在本机内存与本地存储中处理，不经任何服务器 | 不适用 |
| 购买信息 | 否 | 交易由 Apple 通过 App Store 处理，开发者不接触支付数据 | 不适用 |
三、数据在设备上的存储与使用
本应用只在设备本地保存维持正常使用所必需的最少信息，且这些信息不会离开您的设备：
- 界面语言偏好：您选择的界面语言记录在系统 UserDefaults 中，用于下次启动时保持一致。
- 函数表达式与历史记录：您输入的函数、视角与视图设置保存在本应用的本地存储中，仅用于恢复会话状态。
- 导出文件：当您导出图像或数值表时，写入位置完全由您通过系统保存面板（NSSavePanel）或系统分享服务自行选择，应用不会向其他位置写入。
您可以通过删除应用来清除上述全部本地数据；卸载后本应用不会保留任何可恢复的副本，因为不存在任何服务端副本。
四、系统权限说明
本应用仅在下列唯一一种场景下会向系统申请权限，且该权限只用于把结果写入您本人的设备：
| 权限 | 触发场景 | 数据去向 | 您能否拒绝 |
|---|---|---|---|
| 相册写入权限（Photos，addOnly，仅 iOS/iPadOS） | 当您主动点击"保存到相册"导出函数图像时弹出系统授权请求 | 图像仅写入本机相册，不上传、不读取相册中已有内容 | 可以，拒绝后其余功能不受影响 |
| 文件读写权限（macOS：files.user-selected.read-write） | 当您主动导出并选择保存位置时由系统保存面板授权 | 文件仅写入您亲自选定的路径 | 可以，取消保存即可 |
| 其他敏感权限（定位 / 通讯录 / 麦克风 / 摄像头 / 健康 / 日历 / 蓝牙等） | 应用内不存在调用场景，未在配置中声明任何相关用途键 | 不涉及 | 不适用（从未申请） |
本应用不申请定位、通讯录、麦克风、摄像头、健康、日历、蓝牙等任何其他敏感权限，也未使用 IDFA 或请求追踪授权。
五、儿童隐私
本应用不收集任何用户的任何数据，因此也不存在针对儿童的数据收集行为。本应用适合包括儿童在内的所有年龄用户使用（不含广告、不含用户间通讯、不含用户生成内容的上传）。
六、政策变更与联系方式
若未来版本引入任何会改变本政策的数据处理行为（例如新增联网功能），我们将在更新说明中明确告知，并在本页面同步修订政策内容与生效日期；在此之前，本应用将持续保持"不收集任何数据"的状态。
如您对本政策或本应用的隐私实践有任何疑问，请通过 App Store 产品页上的「App 支持」链接（App Store 产品页面 → App 支持）与我们联系。这是本应用唯一且受官方渠道保障的联系方式，我们不会使用其他未经说明的联络途径。
1. Overview
This Privacy Policy explains how Function Visualizer ("the App") handles information in connection with you on iOS, iPadOS, and macOS. The App is provided by an independent developer and is distributed through the App Store as a paid download (USD 4.99, with Universal Purchase for iOS and macOS).
The App's core function is to parse, compute, and plot mathematical functions (explicit functions, implicit equations, and 3D surfaces) entirely on your device. All computation runs on your local CPU/GPU and does not depend on any remote server.
- No data collection: We do not collect, use, or sell any personally identifiable information, and we do not collect device identifiers, location, contacts, health data, browsing history, or any other data category.
- No tracking, no advertising: The App contains no advertising SDK, no attribution SDK, and no cross-app or cross-site tracking capability. It does not declare or use App Tracking Transparency (ATT) keys.
- No network upload: There is no networking code in the App. The macOS version runs inside the system App Sandbox without the network client entitlement, so outbound connections are blocked at the operating-system level.
2. Data We Explicitly Do Not Collect
To make comparison with Apple's App Privacy details straightforward, the table below describes how the App handles each common data category. Every category is "not collected".
| Data Category | Collected | What Actually Happens in the App | Linked to Identity |
|---|---|---|---|
| Contact Info (name, email, phone) | No | No sign-up, no login, no form submission | N/A |
| Location | No | No location permission is requested; no location APIs are used | N/A |
| Identifiers (IDFA / IDFV / fingerprinting) | No | No advertising identifier is accessed; no attribution or analytics service is integrated | N/A |
| Usage & Diagnostics (crash logs, behavioral analytics) | No | No third-party analytics SDK; only on-device UserDefaults for preferences | N/A |
| User Content (expressions, plots, exported images) | No | Processed only in local memory and local storage; never sent to a server | N/A |
| Purchases | No | Transactions are handled by Apple via the App Store; the developer never receives payment data | N/A |
3. On-Device Storage and Use
The App keeps only the minimum information required for normal operation, and that information never leaves your device:
- Interface language preference: stored in the system UserDefaults so your chosen language persists across launches.
- Function expressions and history: the functions you enter, along with view and camera settings, are stored in the App's local storage solely to restore your session.
- Exported files: when you export an image or a numeric table, the destination is chosen entirely by you through the system save panel (NSSavePanel) or the system share service. The App writes nowhere else.
You can erase all of this local data by deleting the App. After uninstalling, no recoverable copy remains, because no server-side copy ever existed.
4. System Permissions
The App requests a system permission in exactly one scenario, and that permission is used only to write a result onto your own device:
| Permission | When It Is Triggered | Where the Data Goes | Can You Decline |
|---|---|---|---|
| Photo Library add-only access (iOS/iPadOS only) | When you explicitly tap "Save to Photos" to export a plot, the system prompt appears | The image is written to your own photo library only; nothing is uploaded and existing photos are never read | Yes; declining does not affect other features |
| File access (macOS: files.user-selected.read-write) | Granted by the system save panel when you choose an export destination | Files are written only to the path you personally select | Yes; simply cancel the save |
| Other sensitive permissions (location / contacts / microphone / camera / health / calendar / Bluetooth, etc.) | No such API is called anywhere in the App, and no related usage key is declared in the configuration | N/A | N/A (never requested) |
The App does not request location, contacts, microphone, camera, health, calendar, Bluetooth, or any other sensitive permission, and it does not use IDFA or request tracking authorization.
5. Children's Privacy
The App collects no data from any user, and therefore collects no data from children. It is suitable for users of all ages, including children (it contains no advertising, no user-to-user communication, and no upload of user-generated content).
6. Changes and Contact
If a future version introduces any data practice that would change this policy (for example, adding an online feature), we will disclose it clearly in the release notes and update this page together with the effective date. Until then, the App will continue to collect no data.
If you have any question about this policy or the App's privacy practices, please contact us through the "App Support" link on the App Store product page (App Store product page → App Support). This is the App's only contact channel, backed by Apple's official infrastructure; we do not use any other undisclosed contact method.
附录：面向开发者的填报对照
本附录用于提交 App Store Connect 时的自检，不属于对用户的承诺条款，正式对外发布时可自行删除。
- App 隐私问卷：所有数据类型均选择"不收集（Data Not Collected）"。
- 上架构建自检：归档产物 Info.plist 中不得出现 NSUserTrackingUsageDescription；若出现该键，Apple 会在提交时硬性拦截，需移除后重新归档上传。
- 权限键清单：iOS 归档仅含 NSPhotoLibraryAddUsageDescription（保存图像到相册）；macOS 为生成式 Info.plist，无任何敏感权限键。
- 其他入口：除本隐私政策页外，建议在 App Store Connect 中同时填写"App 支持 URL"，可指向同一页面或专门的简短支持说明页。