把一个人聚齐
按名字搜播客单集、B 站和 YouTube，勾一批收进同一个专题，按你自己的顺序排。专题钉在首页「深挖」。
已上架 App Store iOS 17+ · 买断制 · 不收集任何数据
想搞懂
一个人？
CastMind 把他散在各处的访谈聚齐，让你听得懂、发得出去。 按名字搜播客单集、B 站和 YouTube，收进同一个专题；有稿时点一句就懂； 听完把记下的东西写成一份自己署名的拆解。
Download on the
App Store
iPhone 扫码
直达 App Store
iPhone 扫码直达 App Store
¥38 一次买断 · 大约一杯星巴克的钱 · 无订阅无内购
- 一次买断 · 无订阅
- 无账号 · 本地存储
- 离线可听可记
- 家人共享
未收集数据
App Store 隐私标签
9.8 MB
安装体积，无广告 SDK
离线优先
原文 · 标注 · 笔记离线可用
中英双语
简体中文 · English
一把尺子
按人，不按节目
想搞懂 Karpathy，今天你得去 Lex 的节目里翻一期，去 Dwarkesh 那里找一期，再去 YouTube 找他自己的长视频。 播客 App 帮不上忙——它们按节目订阅，搜出来的是节目，不是他上过的那一集。CastMind 按人来。
三件事
聚齐，听懂，写出来
CastMind 只做好这三件事，其余的刻意不做。
有稿时，点一句就懂
英文访谈点那一句就能看懂，也能英文对着中文看。节目没给稿，下载后在这台 iPhone 上生成一份。
听完，写一份署名的拆解
点过的句子、记下的时间点按顺序排好，你只写几句自己的看法。一集一份 Markdown，发到你的 X、小红书或公众号。
我自己先用 · 学习统计
这周在啃谁，
一眼看得见
上架前我自己先用了 72 天；上架后又连续 38 天。 左边是上架前的一年累计（157 小时），右边是上架后的近况——这是我的真实学习统计，不是渲染图。
- 今日时长 · 连续天数 · 学习热力图：点开看当日明细，习惯长什么样自己清楚。
- 这周你在听：最常听谁、平台各占多少、Smart Speed 省下的时间，一目了然。
- 订了还没听的，在这里：听最新未听，或先暂停；下面是收听历史和收藏的单集。
数据全部本地存储，可随时导出 JSON，也可以随时删除。
真实截图
App Store 上的 10 张截图，就是全部功能
没有渲染图，没有「即将推出」。点开任意一张放大看。
2 分钟介绍
先看视频，再决定要不要装
发布在 X 上的介绍视频，5,000+ 次观看。录的时候还叫 ContextEcho。
聚齐
搜一个人，
把他找齐
搜一个人的名字，播客、B 站、YouTube 的单集会列在一起。播客能搜到他上过的那一集，不只是整档节目。 勾上要的，一次收进同一个专题。
- 专题：一个人一个合集，跨节目、跨平台，按你自己的顺序排。
- 首页深挖：你钉的那个人在首页第一眼就能看到，「加一集」直接加进去。
- 导入到收听：不想建专题，也可以只进库，打开就能接着听。
听感
Smart Speed 跳静默，
Voice Boost 提人声
Smart Speed 自动跳过语句之间的静默、保持音调自然，省下来的时间计入你的学习统计； Voice Boost 让人声更清晰，长听不累。
- 锁屏 / CarPlay / 控制中心 / 耳机：跑步、通勤、开车、睡前都顺手。
- ±15 秒快进快退：播客、B 站、YouTube 全都支持，全屏也在。
- 0.5–3.0x 精细倍速：常用挡位一点即换，当前单集还可按 0.1 微调。
听得懂
英文对着中文看
全屏逐字稿里，英文下面是中文。选中一句，可以复制、标记、改错词，或再听一遍。 官方没给稿的节目，下载后还能在这台 iPhone 上生成一份，音频不上传。
- 逐句翻译：只译你正在看的那几行，不会整集先翻一遍。
- 改错词：本机听写把名字听错时，直接改那一句。
- 选中就能标记：复制、标记、单句再听，都在这一句上。
偶尔用得上
想留住一句话，
点一下就好
逐字稿里点「留下这一刻」，或在锁屏上记一下。 标记带着时间，也带着正在听的那一句。事后在这一集里找得回。
这不是主流程：用得上就用，不用也不会被催。没有每日提醒，没有小红点。
最近更新 · v1.6.0
ContextEcho 现在叫 CastMind
和 castmind.ai 是同一个名字。老用户不用做任何事。
东西都在原处
你的库、记下的这一刻、下载和设置都没动。以前发出去的合集二维码照常能扫。
视频时长跟着倍速走
不是 1 倍时，原时长划掉，旁边是实际要花的时间。从搜索导入的 YouTube 和 B 站视频也能看到时长。
修好了两处
看视频时点返回不再闪退；B 站登录后停在网页上，也会认出已登录并接着取字幕。
诚实沟通
说清楚做什么、不做什么
买之前先看这里——你的时间和 ¥38 都很贵。
可能很适合你
- 你想系统搞懂某个人到底怎么想的，他的访谈散在好几个节目和频道。
- 英文能听个大概，关键处需要点开看懂。
- 听完愿意写点东西发出去——发到你自己的 X、小红书或公众号。
- 在意隐私：想要无账号、本地存储、不被分析的 App。
暂时不是这个
- 不做推荐流、排行榜、人物浏览目录——你搜你在意的人，我们不替你刷。
- 不让 AI 替你写看法；拆解里你的看法只能你自己写。
- 不做跟读打分、背单词，不是英语学习 App。
- 没有云同步和账号系统（本地优先是刻意选择）。
常见问题
买之前想知道的
CastMind 是什么？
想搞懂一个人？CastMind 把他散在各处的访谈聚齐，让你听得懂、发得出去。按名字搜播客单集、B 站和 YouTube，收进同一个专题；有稿时点一句就懂；听完把记下的东西写成一份自己署名的拆解。
ContextEcho 和 CastMind 是什么关系？
同一个 App。1.6.0 起 ContextEcho 改名 CastMind，和 castmind.ai 是同一个名字。你的库、记下的这一刻、下载和设置都在原处，以前发出去的合集二维码照常能扫。
「我的拆解」是 AI 写的吗？
不是。「这集讲了什么」由你听的时候点过、记下的句子按时间拼成，随便改；「我的看法」只能你自己写，空着就导不出去。导出是一份 Markdown。
收费吗？有订阅或内购吗？
买断制付费 App：中国区 ¥38，美区 $5.99（其他地区以 App Store 当地定价为准）。大约一杯星巴克的钱。一次购买、无订阅、无内购，支持家人共享（最多 6 人）。
支持哪些内容来源？
播客 RSS 与小宇宙链接、B 站视频与合集、YouTube 视频与播放列表，以及网页文章。搜到的单集可以一批导入到收听，或加入合集。
会收集我的数据吗？
不会。App Store 隐私标签为「未收集数据」：无账号系统、无分析 SDK。收听记录、标注和笔记全部存在本机，不上传云端，可导出 JSON 也可随时删除。
可以离线使用吗？
可以。播客单集可下载离线收听；原文、时间戳标注和笔记都可以离线阅读与编辑。没官方稿时，下载后还能在本机生成逐字稿，音频不上传。联网只在你主动刷新订阅、取线上稿或在线播放时发生。
没有官方逐字稿怎么办？
先下载这一集，再点「用本机生成逐字稿」。全程在手机上听写，音频不上传。我用 iPhone 15 Pro Max 转过一集 3 小时 32 分的中文访谈（210MB），大约 6 分钟出稿。对照过，基本上能用。机器听写会有错字，顶栏会标明「未校对」。需要 iOS 26 且设备支持本机语音识别；没有这个按钮，就是这台设备还不支持，不影响正常收听。
和普通播客 App 有什么区别？
普通播客 App 按节目订阅，搜出来的是节目；CastMind 按人，搜出来的是他上过的那一集，B 站和 YouTube 也在一起。它不做推荐流、排行榜和社区。如果你要的是「发现新节目」，它可能不适合你；如果你想把一个人讲透、听完写点东西，它正合适。
什么是 Smart Speed 和 Voice Boost？
Smart Speed 自动跳过语句之间的静默并保持音调自然，省下的时间计入学习统计；Voice Boost 提升人声清晰度，长时间收听更轻松。两者都可以随时开关。
支持哪些设备和语言？
需要 iPhone（iOS 17 及以上），Apple Silicon Mac 也可运行。界面支持简体中文和英文；锁屏、CarPlay、控制中心与耳机控制均已就绪。
现在就能装上，今天先搜一个人
¥38 一次买断，大约一杯星巴克的钱——无订阅无内购。装上之后，第一件事：点收听右上角 +，搜你最想搞懂的那个人。
中国区 ¥38 · 美区 $5.99 · 家人共享
用出问题、有建议？ ，也可以在 X 上私信我。
On the App Store iOS 17+ · One-time purchase · No data collected
Want to understand
someone?
CastMind gathers their interviews from wherever they are, so you can follow them and publish what you took away. Search podcast episodes, Bilibili, and YouTube by name; tap a line to understand it; then write a teardown you'll sign.
Download on the
App Store
Scan with iPhone
to open the App Store
Scan with iPhoneto open the App Store
$5.99 one-time · about the price of a coffee · no subscription
- Buy once · no subscription
- No account · local-first
- Works offline
- Family Sharing
No data collected
App Store privacy label
9.8 MB
install size, no ad SDKs
Offline-first
text, markers & notes offline
Bilingual UI
English · Simplified Chinese
A different yardstick
By person, not by show
To understand Karpathy today, you dig through Lex for one episode, Dwarkesh for another, and YouTube for his own long videos. Podcast apps can't help — they subscribe by show, so search gives you shows, not the episode he was on. CastMind works by person.
Three things
Gather. Understand. Write.
CastMind does these three things well, and deliberately skips the rest.
Gather one person
Search podcast episodes, Bilibili, and YouTube by name. Keep a batch in one collection, in your own order, pinned to Deep Dive on Home.
Tap a line to understand it
When there's a transcript, tap the line, or read English above Chinese. No transcript? Download and make one on this iPhone.
Write a teardown you'll sign
Lines you tapped and moments you marked are laid out in order. You write your own take. One Markdown file per episode, ready for X or your blog.
I used it first · Learning Stats
Who you're digging into,
at a glance
I used it myself for 72 days before it shipped — and another 38 days after. Left is the pre-launch year (157 hours); right is life after listing. My real Learning Stats, not a mockup.
- Today’s time, streak, heatmap: open the day and see whether the streak held.
- What you’re hearing this week: top shows, time by platform, and minutes Smart Speed saved.
- Subscribed, not heard yet: play the newest unheard episode, or pause the show. History and starred episodes sit below.
All data stays on device. Export as JSON, or delete it — anytime.
Real screenshots
The 10 App Store screenshots are the whole app
No mockups, no "coming soon". Tap any screen to zoom in.
2-min intro
Watch the video before you buy
The intro video posted on X — 5,000+ views. It was recorded when the app was still called ContextEcho.
Gather
Search one person,
find it all
Search a person’s name. Podcast, Bilibili, and YouTube episodes show up together — for podcasts, the actual episode they were on, not just the show. Select the ones you want and keep them in one collection.
- One collection per person: across shows and platforms, in your own order.
- Deep Dive on Home: the person you pinned is the first thing you see; “Add an episode” drops straight in.
- Add to Listen: no collection needed — they land in your library, ready to resume.
Sound
Smart Speed skips silence,
Voice Boost lifts voices
Smart Speed trims the gaps between sentences while keeping pitch natural — the time saved counts toward your stats. Voice Boost makes long listening easier on the ears.
- Lock screen / CarPlay / Control Center / earbuds: ready for runs, commutes, driving, bedtime.
- ±15s seek: on podcasts, Bilibili and YouTube — fullscreen included.
- 0.5–3.0x fine speed: tap through common presets or adjust the current episode in 0.1 steps.
Follow along
English above,
Chinese below
In the fullscreen transcript, Chinese sits under the English. Select a line to copy it, mark it, fix a wrong word, or hear that sentence again. If the show never published a transcript, you can still make one on this iPhone. Audio stays on the device.
- One line at a time: it translates the lines on screen, not the whole episode up front.
- Fix a word: when on-device dictation misspells a name, edit that line.
- Select to mark: copy, mark, or replay — on the sentence you selected.
When you need it
Keep a thought
in one tap
Tap “Capture this moment” on the transcript, or mark it from the Lock Screen. The mark keeps the time, and the line you were hearing. Find it later in that episode.
Not the main loop: use it when you want. No daily reminders, no badges.
Recent updates · v1.6.0
ContextEcho is now CastMind
The same name as castmind.ai. Existing users don’t need to do anything.
Everything stays put
Your library, saved moments, downloads, and settings are untouched. Collection QR codes you already shared still work.
Video lengths follow your speed
When speed isn’t 1×, the original length is struck through next to the real time. Videos imported from search show their length too.
Two fixes
Going back during a video no longer crashes. If Bilibili login leaves you on its web page, the app still notices you’re signed in.
Honest scope
What it is — and isn't
Read this before you buy. Your time and $5.99 both matter.
Probably for you
- You want to really understand one person, and their interviews are spread across several shows and channels.
- You follow English mostly, and want to tap the hard lines to understand them.
- You’re willing to write something and post it — on your own X, blog, or newsletter.
- You care about privacy: no account, local storage, no analytics.
Not this, not now
- No recommendation feed, charts, or people directory — you search for the person you care about.
- AI never writes your take; that part of a teardown is yours alone.
- No pronunciation scoring or flashcards; not an English-learning app.
- No cloud sync or accounts — local-first is a deliberate choice.
FAQ
Before you buy
What is CastMind?
Want to understand someone? CastMind gathers their interviews from wherever they are, so you can follow them and publish what you took away. Search podcast episodes, Bilibili, and YouTube by name into one collection; tap a line to understand it; turn what you marked into a teardown you sign.
How are ContextEcho and CastMind related?
Same app. Starting with 1.6.0, ContextEcho is called CastMind — the same name as castmind.ai. Your library, saved moments, downloads, and settings stay where they were, and collection QR codes you already shared still work.
Is “My teardown” written by AI?
No. “What this episode was about” is assembled from lines you tapped and moments you marked, in playback order — edit freely. “My take” can only be written by you; export stays blocked while it’s empty. Export is a Markdown file.
How much does it cost? Any subscription?
One-time purchase: $5.99 US (about the price of a coffee); ¥38 in China. Local pricing varies by storefront. No subscription, no in-app purchases. Family Sharing supported for up to six members.
Which sources are supported?
Podcast RSS and Xiaoyuzhou links, Bilibili videos and collections, YouTube videos and playlists, plus web articles. Search, then add a batch to Listen or to a collection.
Does it collect my data?
No. The App Store privacy label is "Data Not Collected": no account, no analytics SDKs. Listening history, markers and notes stay on your device; export as JSON or delete anytime.
Does it work offline?
Yes. Podcast episodes can be downloaded; text, markers and notes are readable and editable offline. If a show has no official transcript, you can also make one on this device after downloading — audio is not uploaded. Network requests happen only when you refresh subscriptions, fetch a hosted transcript, or stream.
What if a show has no official transcript?
Download the episode, then tap “Make a transcript on this device.” Dictation stays on the iPhone; audio is not uploaded. I ran a 3-hour-32-minute Chinese interview (210 MB) on iPhone 15 Pro Max — about 6 minutes to a full draft. I read it: usable, with typos. The bar stays labeled unproofread. It needs iOS 26 and on-device speech recognition. No button means this device can’t run it — listening is unchanged.
How is it different from a regular podcast app?
Regular podcast apps subscribe by show, so search gives you shows. CastMind works by person: search returns the episode they were on, with Bilibili and YouTube alongside. No feeds, charts, or community. If you want to discover new shows, it's not for you; if you want to understand one person and write something afterward, it is.
What are Smart Speed and Voice Boost?
Smart Speed skips the silences between sentences while keeping pitch natural — saved time counts toward your stats. Voice Boost lifts voice clarity for easier long listening. Both can be toggled anytime.
Devices and languages?
iPhone with iOS 17 or later (runs on Apple Silicon Macs too). The UI is available in English and Simplified Chinese; lock screen, CarPlay, Control Center and headphone controls are all supported.
Install it now. Search one person today.
$5.99 one-time — about the price of a coffee. No subscription, no in-app purchases. First thing after install: tap + on Listen and search the person you most want to understand.
$5.99 US · ¥38 CN · Family Sharing
Questions or feedback? DM me on X.