Privacy Policy
Undersong · effective 31 August 2026
Undersong collects no data and sends nothing anywhere. Everything it keeps stays on your iPhone, and it makes no network requests of any kind.
Audio
The microphone is the app's entire function. Audio is recognised in memory, in real time, on your iPhone. It is never transmitted.
Recordings are kept on the device by default, alongside the transcript of the same conversation, so that you can play a conversation back and hear what was said. They are written into the app's own storage, protected by the system's file encryption while the device is locked, and are never uploaded. About 2 MB per minute is used, and the oldest recordings are dropped automatically once 2 GB is reached.
You can turn this off in Settings › Keep the audio, and it is off automatically whenever Save transcripts is off. Deleting a conversation deletes its recording with it, and Delete every recording removes them all at once.
Transcripts
Finished conversations are saved only while Save transcripts is switched on, which you can turn off at any time. Saved transcripts live in the app's own storage on your iPhone, protected by the system's file encryption while the device is locked. They are never uploaded. Delete all transcripts removes them permanently.
Voices
The app separates the speakers in a conversation and stores a voice print for each — a list of 256 numbers derived from how someone sounds. It is not a recording and cannot be turned back into one. Voice prints stay on the device and can be deleted individually, or all at once, from the People tab.
What we do not do
- No account, no sign-in, no email address requested.
- No analytics, telemetry, crash reporting, or advertising, and no third-party SDK of any kind.
- No device identifiers read — no IDFA, no IDFV, nothing.
- No location access. The app is not linked against the location framework.
- Nothing is shared with anyone, because nothing is collected.
Diagnostic reports
The app can produce a diagnostic report, but only when you ask it to, and it is sent only where you choose to send it through the system share sheet. Reports contain build and device information, your settings, audio-pipeline counters and recent log lines. They contain no audio and no transcript text. Nothing is sent automatically.
Children
Undersong is suitable for all ages and collects no data from anyone, including children.
Changes
If this policy ever changes, the version in the App Store listing changes with it and this page is dated accordingly. A change that introduced any data collection would be stated at the top of this page, not buried in it.
Contact
隐私政策
Undersong · 2026 年 8 月 31 日生效
Undersong 不收集任何数据，也不会把任何内容发送到任何地方。它保存的一切 都留在你的 iPhone 上，并且不发起任何网络请求。
音频
麦克风就是这个应用的全部功能。音频在你的 iPhone 上、在内存中实时识别，绝不会被传输。
录音默认保存在设备上，与同一段对话的文字记录放在一起，方便你回放、听清当时 说了什么。录音写入应用自己的存储空间，设备锁定时受系统文件加密保护，绝不会被上传。每分钟约 占用 2 MB，总量达到 2 GB 后会自动删除最早的录音。
你可以在「设置 › 保留录音」中关闭它；「保存字幕记录」关闭时，它也会自动关闭。删除一段对话 会同时删除它的录音，「删除所有录音」可一次性清除全部。
字幕记录
只有在「保存字幕记录」开启时，结束的对话才会被保存，你可以随时关闭它。保存的记录存放在这台 iPhone 上应用自己的存储空间中，设备锁定时受系统文件加密保护。它们绝不会被上传。 「删除全部记录」会永久移除它们。
声音
应用会区分一段对话中的不同说话人，并为每个人保存一份声纹——由说话方式导出的 256 个 数字。它不是录音，也无法还原成录音。声纹只留在设备上，可以在「人物」标签页中单独删除或 一次性全部删除。
我们不做的事
- 没有账号，无需登录，不索取电子邮件地址。
- 没有分析统计、遥测、崩溃上报或广告，也没有任何第三方 SDK。
- 不读取任何设备标识符。
- 不访问位置信息。应用没有链接位置框架。
- 不与任何人共享任何内容，因为什么都没有收集。
诊断报告
应用可以生成诊断报告，但只在你主动要求时，并且只发送到你通过系统共享菜单选择的地方。报告 包含版本与设备信息、你的设置、音频管线计数器和最近的日志，不包含音频，也不包含字幕 文字。不会有任何内容被自动发送。