# "Is this sister the one who made 미창친?": a blogger who needed four years to get into Korea University turned 3,000 pages of notes into a free app

> Source: https://stringers.io/en/apps/ios_6806178213.html (Stringers / 什么值得做, generated 2026-11-08)
> Stringers answers one question every day: what small product can one or two people build in a few months and actually make money from. Numbers come from 15 databases we collect daily, each with source and date.
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> The creator is an exam-prep blogger with about 9,000 subscribers who had told the story of "3 exam rating to the 99 percentile, years of retaking, then getting into Korea University." A launch video with 120k views and the blog readers brought the first users. Hand-written explanations, only 3 new posts a day, and a fully free tier kept people around, and it launched right in the two months before exams.

[Mobile App](https://stringers.io/en/apps/index.md) · iOS · written 11-6

미

미창친 · Yebin Moon

# "Is this sister the one who made 미창친?": a blogger who needed four years to get into Korea University turned 3,000 pages of notes into a free app

**What it is** A free Korean CSAT (suneung) national-language reading app. It breaks down nearly 14 years of past exam questions sentence by sentence: first you think about how the sentence should be read, then it shows how the author, who scored in the 99 percentile, thought about it. It also has vocabulary, a journal and study check-ins.

**Why it took off** The author is a test-prep blogger with about 9,000 subscribers who told the story of getting a 3 grade with a 99 percentile score after repeating years and then getting into Korea University. A launch video with 120k views and readers of the blog brought the first users. Handwritten commentary by the author, only 3 posts a day, and everything being free kept people around, and it coincided with the last two months before the exam.

**C** **How you could follow it** You can't copy the app itself. If you're a top scorer in some exam with followers, or can partner with a blogger like this, the approach is: turn the author's notes into a tool with sentence-by-sentence interaction, release new content in limited daily amounts, use the author's own launch videos to cold-start, and time the launch for the two or three months before the exam.

C grade: the traction came from the author's own story, credibility and an existing audience, which a typical indie developer doesn't have. Similar apps without that persona-driven angle are stuck at single-digit ratings. The product is fully free and highly seasonal, so the "someone with an audience turns their notes into a tool" playbook is worth learning, but copying it directly isn't worth much. Word in small circles

Data (updated daily) · First launched 2026-09-02 · Korean rating 271 · 11-08 charted in 1 stores

iOS · best category chart rank · by store

Data 2026-11-02 → 2026-11-08 (7 days, 4 observations). Lower rank is higher; gaps mean it wasn't charted that day

iOS · rating count · Korea

Data 2026-11-02 → 2026-11-08 (7 days, 4 observations). Apple doesn't publish download counts; rating growth is a proxy for downloads.

미창친 is a Korean CSAT (수능) national-language reading app, launched in Sep 2. It's the only app under its developer account. Two weeks before the Nov 19 exam, it has 255 ratings at 4.9 stars in the Korean App Store, adding 87 ratings from Nov 2 to 6 (4 days). Five or six similar 수능 국어 apps launched this year, and none has more than 20 ratings. It didn't take off because its features are impressive: its creator was already a study-prep blogger with a following.

### "Only a month left until the suneung and I'm only now..."

Oct 3, a high school senior left a five-star review of 미창친 on the App Store:

> "제 과외 선생님이세요ㅜㅜㅜ 수능 한달 남았는데 이제서야 기출분석하는 방법을 알아낸 것 같아요... 진짜 과외하는 것처럼 하나하나 다 나와있어서 너무 좋아요" ("You're my tutor! With a month to the CSAT, I've finally figured out how to analyze past papers... Everything is laid out step by step, just like a real tutor. Love it.")

The same tone runs through nearly every review that month. 「이게 왜 무료?」 (Why is this free?10-07); 「학원보다 나은 듯」 (Feels better than a cram school, 10-21); 「시중에 나온 다양한 인강, 독학서 모두를 다 이기는 앱」 (Beats every online course and self-study book on the market, 10-24). Someone also wrote in Oct 13 how they found it: 「개발자님 유튜브로 어플 접하게 됐는데요」 (I found the app through the developer's YouTube channel).

That line about the developer's YouTube channel is why this app took off.

### What it is

A Korean SAT reading app. It takes past questions from the last 14 years set by the KICE (the Korean exam authority) plus every passage from the EBS-linked textbooks and breaks them down sentence by sentence. For each line, you first write or pick what you think is going on, then it reveals how the author was reasoning at that point. The commentary also links past exams across years: when it covers the Bretton Woods passage from 2022, it brings up the "exchange rate overshooting" question from 2018.

There are also 2,345 vocabulary words, 29 articles on psychology and study methods (the "Library"), a diary with templates for "perfectionism" and "helplessness," and a study room where you post daily photo check-ins. Three rule violations and you're removed. Only 3 new questions are released each day.

Completely free, no in-app purchases, no subscription. The store page says "Everything is free for now" (지금은 전부 무료입니다). The web version has the same features as the Android version, and Google Play shows 1,000+ downloads (11-06).

### Who makes it

Store description opener: 「국어는 재능이라고 믿었습니다. 만년 3등급이던 제가 평가원 백분위 99를 받기 전까지는」 (I used to believe Korean was talent. Then I was a permanent 3 grade, and then I scored 99 percentile on the KICE mock exam.)

On YouTube and Naver Blog, the author goes by "Michangchin" and "Dalbin." Their story is about their own exam prep: they went from grade 3 in Korean to a percentile of 99, repeated the year several times, had one year's exam score voided, fell into depression for a while, and finally got into Korea University. The channel has about 9,190 subscribers, and the two videos telling this story before launch have over 180k views each (YouTube, 11-06). They say they wrote 3,000 pages of notes while studying, and stayed up 15 nights in a row during the final push to finish the app.

### Where users come from

- **Its own blog and channel** is the main engine. Aug 25 it teased the launch on its Naver blog, Sep 3 it posted a Q&A, and several early reviews on the official site are tagged "네이버 블로그 2026.8.29–9.4". The launch video from Sep 20, "고려대 합격 영상 올리고 9개월간 잠수탔던 이유" (why I vanished for 9 months after posting the Korea University admission video), got about 122k views and 191 comments, and the first line of its description links iOS, web and Android. The top comment, "이 언니가 미창친 만든 사람임????" (wait, is this the person who made 미창친?), has 133 likes.

- **App Store search** : search "Suneung Korean," "Korean past exams," or "Nonliterary reading," and it ranks in the top 1–4 (iTunes search, 11-06). Similar apps have almost no ratings, so it's easy to climb. Some reviewers said they "found it by accident while searching for Suneung."

- **Word of mouth in exam-prep communities** : on Orbi (Korea's biggest exam-prep forum) there are posts like "Anyone know the YouTuber Michangchin??"; in reviews, people say "I recommend it to my friends every day."

- **Timing** : launch day fell on the September mock exam, about 10 weeks before the Suneung, exactly when students are most anxious and most eager to go back to past questions. Ratings clearly accelerated in November.

- No paid ads seen, no discussion on X, no media coverage.

### Why this one and not the others

Plenty of apps do "line-by-line past-question explanations," but none of the others took off (Korea App Store, 11-06):

| App | Launched | Score | Approach |
|---|---|---|---|
| 미창친 | 2026-09 | 255 | Real people writing out their reasoning line by line, plus diary and check-ins |
| 독기 | 2025-10 | 19 | Past questions filtered by subject, delivered as PDFs |
| 김은광 수능국어 | 2026-07 | 9 | Practice apps built around a famous teacher's brand |
| 독파: AI 수능 국어 | 2026-08 | 3 | Self-made questions with AI grading |
| 비수다 | 2026-07 | 2 | Also "3 grade + nonliterary past questions," nearly the same positioning |
| 오르조 ORZO | 2020 | 10,748 | Multi-subject past-question practice platform that explains why answers are right |

Bisuda is positioned almost exactly like it, yet has only 2 ratings. The difference comes down to two things:

1. **Where the first users came from** : she had a group of viewers who had heard her story and sympathized with her, so one video brought in tens of thousands of clicks. Other solo developers didn't have that.

2. **Who wrote the content** : she wrote every explanation herself, line by line, in first person, with the perspective of "this is exactly how I got it wrong back then." Users buy into "how the person who scored a 99th percentile thinks," and nobody else can borrow that credibility. AI can also explain line by line: in Nov 4, dowazo.ai promoted an AI version of "past questions explained line by line" on Instagram, but AI writing doesn't carry this person's voice.

What keeps people around are a few other things: only 3 passages are released a day, which forces you to come back daily; the diary and psychology articles make it feel like someone supporting you through exam prep, and a user said "The Michangchin Library helped me a lot when I was wavering" (我动摇的时候,서재 帮了很多,11-05); user suggestions get implemented the same day, and one reviewer specifically wrote "Improvements get applied right away" (개선사항이 바로바로 반영).

### Is anyone copying it?

No direct copycat app yet. dowazo.ai's AI line-by-line positioning is very close, but there's no sign it was inspired by this one. Almost nobody outside knows about it: no media coverage, 0 posts on X, and no revenue to show off, because it doesn't charge. Only the Korean exam-prep community knows it.

### If it were you

**One-line verdict** : you can't replicate this app itself, because it runs on the author's story and audience. What you can learn is the playbook: someone with an audience turns their own notes into a tool.

**Who it suits** : someone who already scored top marks in a particular exam and has a few thousand to tens of thousands of followers on YouTube, Bilibili, Xiaohongshu, or a blog; or a developer who can partner with a creator like this and handle the building. The exam can change: China's gaokao Chinese or English reading, Japan's Common Test, TOEFL and IELTS reading, various professional certifications.

**Who it doesn't suit** : developers with no content creator behind them who only want to build a "line-by-line explanation" feature. Bisuda and Dokgi already show that the same format without a persona or audience stalls at single-digit ratings; AI line-by-line explanations are already being built, so the format alone can't hold the position. Also, the business doesn't make money yet: it's entirely free, and the author mentioned wanting a paid check-in study room, but hasn't built it because of Apple's commission.

**How to do it:**

1. Have the creator first, then the app. The creator needs a clear transformation story ("from X points to Y points") and a large body of their own notes or explanations.

2. Keep each learning unit tiny: one sentence, one small question. Let users think first, then show the author's thinking.

3. Release new content in limited daily amounts, wrapped in diary, check-ins, and psychology articles. It's cheap to build and does the most to bring people back every day.

4. App, web, and Android launch on the same day, with all three links in the launch video's description.

**How it got users** : the author's own launch video plus blog previews were the entire cold start. Tell regular readers first, then go public. After that, it relied on App Store search (almost nobody competes for keywords in niche exams) and word of mouth in exam-prep forums. Launch timing was set for two to three months before the exam, aligned with mock tests.

**Is it too late** : there's no window; this is a playbook. But it's highly seasonal, so to target the next cohort of test-takers, launch about 3 months before the big exam.

**If you want to charge** : route payments through the web to avoid Apple's commission. Paid check-in study rooms, handouts, and tutoring referrals are all possible directions, but nobody has proven one yet (inference).

**What would mean I got it wrong** : ① after the Nov 19 Suneung, daily new ratings stay at over a dozen a day, and another wave comes after the new third-year students start school in March, which would show it's more than a pre-exam sprint tool and the accumulated word of mouth brings in new users on its own; ② a similar app with no creator persona (like an AI line-by-line explainer) gets hundreds of ratings in Korea, which would show the format works on its own and doesn't require a real person.

### Data and sources

- Rating counts, growth rate, and chart ranking: Korea App Store, 11-02 to 11-06; free Education chart around #91–103.

- Store description, version, and price: Korea App Store listing, 11-06.

- Verbatim reviews: Korea App Store user reviews, 10-03 to 11-05; YouTube launch video comments.

- Video views and channel subscribers: YouTube, checked 11-06.

- Blog previews and Q&A: Naver Blog dpqlsans, 8-25 and 9-03.

- Similar apps' ratings: Korea App Store search, 11-06.

- Android downloads: Google Play page, 11-06.

- Suneung date: KICE 2027 academic year Suneung basic plan (2026-11-19).

- Total user numbers, actual usage of the Android and web versions, and the copyright status of the EBS passage commentary aren't public, so this piece makes no claims about them.

[iOS store page ↗](https://apps.apple.com/app/id6806178213)

**Research notes: competitor table, acquisition evidence, full research report**

Competitors

| Name | Where | Launched | Scale | How it differs from this one |
|---|---|---|---|---|
| 오르조 ORZO | iOS | 2020-11 | iOS 10,748 rating, Korea Education free chart #2,7, +81 in a day | Multi-subject past-question practice platform (iPad with stylus) that explains why answers are right; Michangchin covers only Korean and explains how to think about every sentence |
| 풀다 / 기출탭탭 / 쏠브 | iOS | 2020–2022 | 2,495 / 1,375 / 701 ratings | Comprehensive question bank with AI explanations, not a real person walking through their reasoning line by line |
| 비수다 - 국어 3등급 비문학 기출 독해 | iOS | 2026-07-29 | 2 ratings | Nearly identical positioning (3 grade, nonliterary past questions), but no creator persona or audience, so it didn't take off |
| 독기: 수능 국어 독서 기출문제 | iOS | 2025-10-14 | 19 ratings | Filters past questions by subject and provides PDFs, no line-by-line explanations |
| 독파: AI 수능 국어 | iOS | 2026-08-17 | 3 ratings | Self-made questions with AI grading of short answers; doesn't use past exams, and has no real person's reasoning process |
| 김은광 수능국어 | iOS | 2026-07-21 | 9 ratings | A practice app built around an individual famous teacher's brand; neither the audience nor the interactive format took off |
| 레서 Lesser | iOS | 2022-05 | 110 ratings | Uses AI eye-tracking to train reading skills for primary and middle school students, not aimed at Suneung past questions |
| dowazo.ai 수능국어연구소 | Web | 2026-11 | Unknown | Uses AI for line-by-line explanations of past questions; Michangchin is handwritten by a real person and adds emotional support and check-ins |
| Megastudy / Daesung Mymath Korean video courses and workbooks such as "Mae3bi" | Other | Years | Industry mainstream | Paid video courses and books; Michangchin is free, interactive, and breaks down each sentence, and users compare it directly to video courses and workbooks in their reviews |

Where users come from

- **Verified** **YouTube, own channel** : launch video "Why I disappeared for 9 months after posting my Korea University admission video" (2026-09-20), 121,976 views, 191 comments, with iOS, web, and Android early-access links in the first line of the description; channel has 9,190 subscribers, and the two earlier story videos each have 180k+ views (YouTube Data API 11-06)

- **Verified** **Naver Blog (Dalbin / dpqlsans)** : 8-25 posted the launch preview, 9-03 posted the Q&A, announcing to blog neighbors first; the website's review wall has 8-29 to 9-04 reviews tagged "Naver Blog"

- **Confirmed** **App Store search** : a YouTube comment says "I searched 수능 on the App Store today and 미창친's app came up"; iTunes results for "수능 국어", "국어 기출", "비문학" rank it #1–4

- **Confirmed** **Study communities and word of mouth** : an Orbi thread "Anyone know YouTuber 미창친??"; a comment says "recommended it to my friends constantly"; edu.dasfl.com published an SEO guide (9-13)

- **Confirmed** **Exam-season timing** : 9-03 launched on the same day as the September mock exam, about 10 weeks before the November 수능; reviews accelerated in November

- Inferred **Publisher endorsement (매3비 scholar)** : 키출판사's 매3 blog featured her study method before the app launched; whether it drove app downloads is unverified

- Inferred **Paid ads** : no evidence found (ad libraries don't track this app)

## 미창친 (Michangchin): why it broke out

> Korean iOS education app, charted on 2026-09-02, developer Yebin Moon (this account has only 1 apps). Research date 2026-11-06.

### Bottom line

Its growth didn't come from the app alone. It came from **a 수능 study YouTuber who already had an audience moving her persona and content into the app** . "미창친" has about 9,190 YouTube subscribers and runs the study blog "달빈" on Naver. Over three years she built a deeply relatable personal story: going from a 3 grade to the 99 percentile, repeating the exam 3–4 years, a "수능 invalidated" incident, depression, and finally getting into Korea University. At launch, a release video with 120k views plus her blog readers brought in the first users. What keeps them is her own sentence-by-sentence explanation of her thinking, which is hard to replicate. A pace of only 3 passages a day and everything free also helped, and reviews are almost all positive (4.9 stars). Five or six similar indie 수능 국어 apps launched this year, and none got above 20 ratings. That shows the difference is content and the author's credibility, not features.

### 1. Basic data

| Metric | Value | Source |
|---|---|---|
| iOS ratings | 160(11-02) → 247(11-06), +4 in 87 days, about 22/day | appstore library app_day, kr |
| Current rating | 255 ratings, 4.89 stars; version 2.0.4 (11-04 updates) | iTunes lookup,11-06 |
| Charts | Korea education free chart #91 (store page) / best in library #103 | App Store page; appstore library |
| Growth rank | Fastest rating growth in Korea education over 7 days, ranked 9. Ahead of it: Duolingo, 열품타, Speak, Praktika, 말해보카, 유니브 AI, Toca Boca, Falou. None of them is a dedicated 수능 app. 오르조 gained +81 in 7 days, less than this app | appstore library app_profile, 11-06 |
| Android | Play package name kr.plannercert.app, "1k+ downloads". September originally distributed it through an early-bird form before the official listing | Play page (fetched via Jina, 11-06) |
| Web version | app.michangchin.com, same features as the app | Website |
| Paid | All free, no in-app purchases or subscriptions ("Everything is free for now") | App Store description |
| Review pace | An older snapshot of the official site shows 111 ratings; search snippets show 205; 11-06 shows 255. That means it roughly doubled since late October | Official site, Jina search snippets, iTunes |

### 2. Competitors

**Similar indie apps (launched in the last 2025–2026 years, all free, none took off):**

- **김은광 수능국어** (2026-07-21,9 ratings): a well-known tutor's personal brand, practice-question focused.

- **독기: 수능 국어 독서(비문학) 기출문제** (2025-10-14,19 ratings): real past exam questions filtered by domain, with PDFs.

- **독파: AI 수능 국어** (2026-08-17,3 ratings): self-made questions plus AI grading of short answers.

- **비수다 - 국어 3등급 비문학 기출 독해** (2026-07-29,2 ratings): almost the same positioning, "3 grade + non-fiction past-exam reading."

- **줄줄 AI** (2026-10-08,1), **꾸준히 국어** (2026-10-19,0), **수능 국어 (별책)** (2026-10-28,1).

(Data above from iTunes Search, kr, 11-06.)

**Big players and established products:**

- **오르조 ORZO** (Sling, 2020, iOS 10,748 rating, education free chart #2): an all-subject past-exam practice platform, works on iPad with a stylus, marketed as "1M users." It went free for 2022 years and reached #1 on the App Store. It focuses on doing problems, not on explaining how to think through each sentence.

- **풀다 / 기출탭탭 / 쏠브** : past-exam question banks with AI explanations, covering multiple subjects.

- **레서 Lesser** (2022,110 ratings): AI Korean-language tutoring that uses eye tracking to see how you read, aimed at reading skills for middle and high school students.

- **이모 (이감 모의고사)** (2023,231 ratings): companion app for a paid mock-exam brand.

- **Online courses and workbooks** : Megastudy, Daesung MyMath and other Korean-language star-teacher courses, plus print workbooks like 《매3비》. These are the real rivals competing for the same budget and time. User reviews compare it to them directly: "an app that beats all the various online lectures and self-study books on the market."

- **dowazo.ai "수능국어연구소"** (web, 2026-11-04 Instagram reel): "2017–2028 past-exam passages explained one sentence at a time," AI-generated and free. Its pitch is nearly identical to 미창친's, except the explanations are written by AI.

**Takeaway:** The "수능 국어 + past exams + app" space is crowded, but a product where a real person in the 99 percentile writes out their own thinking for every sentence and turns it into interactive choices is unique on the App Store. Other indie developers have built question banks or AI explanations, and none of them took off.

### 3. Growth tactics (where users come from)

1. **The creator's own audience (main channel, confirmed)**
    - YouTube @Michangchin: opened 2024-06, 9,190 subscribers, 550k total views, only 7 videos. Top videos: "Story of a Third-Year Test Taker | 수능 Results" (2025-1.19M), "Update from a YouTuber Whose 수능 Was Invalidated" (2026-2.19M). These videos built a sympathetic audience. (YouTube Data API, 11-06)
    - Release video "Why I went dark for 9 months after posting my Korea University admission video" (2026-09-20): **121,976 views, 1,879 likes, 191 comments** . The first line of the description links to iOS, the web version, and the Android early-bird form; the video includes 5 feature demos. Top comments include "Isn't she the person who made 미창친????" (133 likes) and "52 days until 수능… I'll try 미창친."
    - Naver blog dpqlsans ("달빈"): she calls it "my home turf is the blog." She posted a launch preview on 8-25 and a Q&A on 9-03, telling her neighbors (이웃) first before announcing on YouTube. Many entries in the official site's review wall are labeled as coming from "Naver blog 2026.8.29–9.4," which suggests her blog readers were among the earliest users around launch.

2. **App Store search (confirmed, volume unknown)** : a YouTube comment reads "I searched 수능 on the App Store today and 미창친's app came up." For "수능 국어," "국어 기출," and "비문학" on iTunes, it ranks #1–4. Similar apps have almost no ratings, so it's easy for this one to rank.

3. **Study community word of mouth (small circle, partly confirmed)** : Orbi (오르비) has threads like "Anyone know YouTuber 미창친??" and "미창친 update." Users write "I recommend it to my friends constantly" and "hope you buy the dip soon." A third-party SEO blog, edu.dasfl.com, also has a "수능 국어 미창친 guide" (2026-09-13).

4. **Publisher tie-in (indirect)** : she is a "2026 매3 scholar" for 키출판사, publisher of the workbook 《매3비》, and 매3's official blog has featured her study method. This endorsement predates the app. Whether it drove app downloads is unverified.

5. **Timing** : launched 9-03, the same day as the September mock exam. The 2027 academic-year 수능 (2026-11-19; by past convention the third Thursday of November, unverified) is 10 weeks away, right when test-takers are most anxious and most in need of "past-paper review." Rating growth picked up in November (4 days, +87), in line with pre-exam sprint seasonality.

6. **What I didn't find** : no paid ads (Meta and TikTok ad libraries showed nothing this round, and they don't track small apps like this), no discussion on X (x-radar: 90 days, 0 posts), no media coverage, no chart-pushing or limited-time free promotions.

### 4. Why users stay

- **Real content, and unique** : 14 years of 평가원 exams plus every EBS passage. For each sentence, the user first chooses "what you're thinking right now," then the "미창친 thinking" is revealed. Explanations link past exams across years; for example, the "Bretton Woods" passage from 2022 references "exchange rate overshooting" from 2018. User reviews: "I found reading points I missed in passages I'd read 5 times" and "Tutoring centers give passage explanations like this too, but this one's quality is much better, which surprised me."

- **Only 3 passages a day (stated in the Q&A)** : she says releasing everything at once would be better for promotion, but she chose 3 a day so people read deeply. This is actually a strong daily-active mechanism, since users come back every day.

- **Emotional companionship layer** : the "서재" (study) section has 29 articles on psychology and study methods. "일지" (journal) has templates for perfectionism, feeling powerless, and so on. "플래너방" (planner rooms) are organized on a schedule, with morning and evening photo check-ins, and three violations get you removed. These turn a question app into a study companion. Some non-test-takers also installed it for the journal feature (YouTube comments).

- **Fast developer response** : reviews say "improvements are applied immediately," and the app is already at version 2.0.4.

- **Free** : almost every positive review says "I can't believe it's free," and someone says "I'd buy it even if it cost 100 won."

### 5. Differentiation

| Dimension | 미창친 | Typical competitors |
|---|---|---|
| Study unit | One sentence, and what to think about while reading it | One question, and why this answer is correct |
| Commentary source | Handwritten by her, with a first-person perspective and links between the questions and the real exam | Official answer-key explanations / AI-generated |
| Interactive | For each sentence, pick or write your own take first, then check the answer | Read the explanation after finishing the questions |
| Extras | 2,345 vocabulary words, psychology articles, journal, check-in rooms | Timer, wrong-answer notebook |
| Source of credibility | A real person with a story (3 grade → 99) | Company brand / famous teachers |

**Is that gap because of how it was built?** Half of it, yes. The "sentence-by-sentence thinking process" keeps users around, and gets them to write long reviews and recommend it on their own (4.9 points, lots of long reviews). But what brought users in the first place was the creator's own audience and persona. The evidence: apps with nearly identical positioning (비수다, at 3 grade plus non-literature exam questions) and 독기 sit at single-digit ratings. An AI version of "sentence-by-sentence commentary" (dowazo) has already appeared, so the format alone can't hold the position. What holds it is the trust that "this is her own thinking," plus the hand-built workload (she says she has 3,000 pages of prep notes, and during the dev sprint she pulled 15 consecutive all-nighters).

### 6. Visibility and copycats

- **Visibility** : it's spreading within a small circle. The Korean exam-prep community knows it (YouTube subscribers, neighbors on her Naver blog, Orbi). No press coverage, 0 posts on X, and no revenue to speak of (it's entirely free).

- **Copycats** : no app has directly copied it yet. dowazo.ai pushed an AI version of "sentence-by-sentence explanations of past-exam passages" at 11-04. The positioning is close, but there's no sign it was inspired by this one, so it's only a suspected copy.

### 7. What others can borrow

- **"A KOL's own content assets → turned into a tool"** : 3,000 pages of notes, past blog posts and study methods became the library and sentence-by-sentence commentary inside the app. The cold start came from one launch video with a story behind it, no paid spend.

- **"Limited daily release" instead of "full release at once"** : 3 passages a day is both a teaching philosophy and a retention mechanism.

- **Wrapping the hard content in emotional support** : the exam-prep crowd is very anxious, so diary templates and check-in rooms are cheap to build, yet they keep coming up in reviews as a plus.

- **App, web, and an Android early-bird signup form all launched at once** , catching all the traffic from the videos.

- **The monetization path hasn't been walked yet** : she mentioned that her earlier offline check-in rooms used a "10k won deposit" model, which hasn't been brought into the app because of Apple's commission. Likely directions: paid check-in rooms (via web payment), paid EBS commentary, and tutoring referrals.

### 8. Risks and unknowns

- **Strong seasonality** : demand is tied tightly to the 11-19 Suneung. Expect traffic to drop after the exam. Whether it carries into next year depends on whether the new batch of 2028 test-takers trusts her.

- **Copyright** : in Q&A she herself mentions "저작권 문제" (copyright issues) around EBS passage commentary. The description already says "ebs 전 지문" (all EBS passages), but whether licenses were obtained is unverified.

- **Actual Android numbers** : Play only shows 1K+, and the true ranking and web user count don't reveal much; total user base is unknown.

- **Other unverified items** : details of the "Suneung invalidation" incident; whether there's a co-developer (she says a senior from Korea University); whether there's paid promotion (the ad libraries don't track this app, so not finding it doesn't mean nothing was spent).

### Sources

- appstore library (agent-im, DuckDB): app_day 2026-11-02/11-06; app_profile kr education category, 11-06

- iTunes Lookup / Search API(kr,2026-11-06)

- App Store page [apps.apple.com/kr/app/id6806178213](https://apps.apple.com/kr/app/id6806178213)

- Official site [michangchin.com/](https://michangchin.com/) (includes a praise wall and blog/video sections)

- Naver blog [m.blog.naver.com/dpqlsans/224389984988](https://m.blog.naver.com/dpqlsans/224389984988) (8-25 launch preview), [m.blog.naver.com/dpqlsans/224399167878](https://m.blog.naver.com/dpqlsans/224399167878) (9-03 Q&A: 3 passages a day, check-in room rules, Apple's commission)

- YouTube Data API: channel UCzRH8u1ZI8D_ghc9bPamzcQ; video l3a9KYmbyvQ and its comments

- Google Play [play.google.com/store/apps/details?id=kr.plannercert.app](https://play.google.com/store/apps/details?id=kr.plannercert.app)

- Orbi: [orbi.kr/00077297492](https://orbi.kr/00077297492), [orbi.kr/00077558184](https://orbi.kr/00077558184)

- edu.dasfl.com "Suneung Korean Language Micha-chin Guide" (2026-09-13)

- 매3 blog [m.blog.naver.com/keymae3/224234468441](https://m.blog.naver.com/keymae3/224234468441)

- dowazo.ai Instagram reel [www.instagram.com/reel/DfUNs_YhmRA/](https://www.instagram.com/reel/DfUNs_YhmRA/) (2026-11-04)

- Orjo coverage: byline.network 2022-11

- x-radar search for "미창친", 90 days: 0 posts

This article was written by AI from public data and the data we collect daily. Numbers are sourced, and inferences are labeled.