A one-star review "saw it on TikTok, downloaded, deleted": the Korean height-prediction app 숨키, 7 ratings squeezed into Top Grossing #43
What it is A height-prediction app by a Korean indie developer: you enter your parents' heights, it calculates your "potential height", then sells a subscription check-in plan for sleep, nutrition, stretching and posture. There are no free features.
Why it's taking off It copies the template of the recently widely covered GoTall; the Top Grossing bar in Korea's category is low; the English original was never localized to Korean; and teen-heavy TikTok traffic pays at a high rate, so a few dozen subscriptions is enough to break into the top 50.
CHow you could follow it Don't follow it specifically. If you already run a quiz + paywall + TikTok paid-acquisition pipeline, pick a language where the English original hasn't been localized and local height-anxiety messaging already exists, open a site there, and keep some features free.
- Data (updated daily) · First launched 2026-09-11 · Korean rating 7 · 11-08 charted in 1 stores
iOS · best category chart rank · by store Data 2026-10-28 → 2026-11-08 (12 days, 12 observations). Lower rank is higher; gaps mean it wasn't charted that dayiOS · rating count · Korea Data 2026-10-28 → 2026-11-08 (12 days, 12 observations). Apple doesn't publish download counts; rating growth is a proxy for downloads.
숨키 (Sumki) is a height-prediction app from a sole proprietor in Pyeongtaek, Korea: enter your parents' heights, get your "hidden height", and everything else is behind a subscription. It is almost a direct Korean translation of the US app GoTall (reported at $100k a month). Less than two months after launch, it reached #43 in Korea's App Store Health & Fitness Top Grossing chart in Nov 6. But don't be fooled by the rank: it has 7 ratings in total at 1.6 stars, and October global revenue is estimated at under $5,000. It proves the playbook can work in a small-language market, but that patch is already crowded and not worth chasing specifically.
The review from Oct 3
On Oct 3, the first and so far only written review of 숨키 appeared on the Korean App Store: 1 stars, with a five-character title: "틱톡보고까름" (saw it on TikTok, downloaded, deleted). The body is in a teenager's voice:
"You're not going to make it free anyway, so why have a close button? If you're charging for everything, just set the app to paid from the start. Nothing is free to use."
Five days later the developer replied: "The features we offer for free go up to 'confirming your maximum potential height'."
This exchange lays out the whole business: users come from TikTok, complete a long quiz, see a height number, and then hit the paywall.
What it is
The store subtitle reads: "Big-data-based potential height prediction! Use sleep and posture habits to catch the golden growth window."
How it works: enter parents' heights, age, weight, whether you have growing pains → get your "maximum potential height" → a "growth plate closing countdown" → daily check-ins for early sleep, drinking milk, stretching and posture, with the "potential height" number on screen rising as your check-in completion rate goes up. The Android store page literally says "도파민 넘치는 쾌감" (dopamine-rush pleasure).
Monetization is subscription-only, no freemium: weekly ₩5,500 (about $4), monthly ₩19,000, annual ₩29,000 (App Store Korea storefront, 11-06). The store description itself states "no free-use mode", "does not diagnose, measure growth plates, or guarantee height gain".
The developer is Remaster Archive, registered on the store as a sole proprietorship in Pyeongtaek, Gyeonggi-do, and its website also lists a fitness and diet check-in app. The iOS version launched Sep 11, updated Nov 2 to 1.1.4; the Android version is also live, with Google Play showing 1,000+ downloads.
High rank, tiny pool
| Date | Korea Health & Fitness Top Grossing |
|---|---|
| 10-28 | #102 |
| 11-01 | #85 |
| 11-02 | #72 |
| 11-05 | #139 |
| 11-06 | #43 |
App Store Korea storefront. Over the same period it sat well outside the top 100 on the Top Free chart, and only briefly hit #38 in Oct 25 (per a third-party hourly rank tracker).
Low on Top Free and high on Top Grossing means few downloads, but a high share of those downloaders pay. On Nov 6, the apps around it were StepsApp with 22k ratings and a home-workout app with 4,900 ratings. Korea's Top Grossing bar is low, so a few dozen subscriptions a day probably gets you into the top 50 (inferred). Even the #43 spot was a single-day peak; the day before it was at 139.
Real scale: ratings went from 28 6 in October to 6 7 in November, only one more in ten days. Appfigures estimates October global downloads under 5,000 and after-tax revenue under $5,000. It's localized in 12 languages, but only the Korean store has ratings; the US and Japan stores both show 0.
Why now, why Korea
The template is ready-made. The US GoTall was built by a 20-year-old NYU student: a 47-screen quiz, a 91% paywall reach, and 10 TikToks posted a day. An Aug 27 teardown article said its peak month was $148k, and in Sep 2 Starter Story retold it on TikTok. 숨키 launched in Sep 11 with the same structure: quiz → "potential height changes with check-ins" → hard paywall. It is inferred that it was built after reading the coverage, but the timing is too tight to be coincidence.
The English original didn't hold Korea. On the same day, GoTall ranked #180 on Korea's Health & Fitness Top Grossing, and HeightMax, which changed its store name to Korean, ranked #166. A Korean-native version priced in won doesn't need much revenue to rank above them.
Korean users are primed for this messaging. "성장판 닫히기 전" (before the growth plates close) and "골든타임" (golden window) are long-running themes in Korean TikTok growth clinic and supplement promotion; search almost anything and you'll find them. 숨키 wrote this anxiety straight into its copy, even naming the app as an abbreviation of "숨은 키" (hidden height).
Where users come from
The only thing confirmed is TikTok: the one-star review says so itself. The app's privacy label declares "tracking you with identifiers", which means ad attribution is connected, and it is probably buying ads (inferred). But searching TikTok for "숨키", "sumki", "잠재키" and "키 성장 앱" turns up no official account and no creator-promo videos; the Meta ad library has nothing either. Whether it's paid traffic or anonymous content accounts is unverified.
The rest is in-store: the name is stuffed with search terms like "키 성장 예측" (height growth prediction) and "습관" (habit), and under "You may also like" it appears alongside a string of similar height apps. There's no press coverage, and nobody is discussing it on X or Korean blogs.
Who it's competing with
| Product | Scale (11-06) | How 숨키 differs |
|---|---|---|
| GoTall | 6,784 ratings on the US store; publicly reported $100k+ monthly; #180 Top Grossing in Korea | The original, in English; part of it still works with the paywall closed |
| Taller | 17k ratings on the US store, 1,888 in Vietnam; ranked in dozens of small-country category charts | The largest in the niche; lots of matrix accounts flooding TikTok with videos |
| HeightMax | 126 on the US store; #166 Top Grossing in Korea | Foreign team, also changed the Korean store name |
| UPARO | Launched 9-28, 0 ratings; creator videos with discount codes reaching 540k–1.43M views each | A same-period newcomer, going the creator route |
| 골연령 (bone age) | Launched 9-17, #122 Top Grossing in Korea | A same-period Korean copycat, rebranded with the "bone age" framing |
| BeTaller, TallPath and others | Launched 8–October, all very small | Vietnamese and Danish teams, cloning GoTall across countries at the same time |
| 아이키기록 | 160 ratings at 4.69 stars, ₩7,700 one-time purchase, top 41 on Korea's paid chart | An established Korean local, for parents tracking children's growth curves |
In the "You may also like" section of the Korean store you can still surface small products with single-digit ratings like 키디, 그로비 and 키 성장 AI 코치. Feature-wise they're all the same; 숨키's only real edge is the Korean language and Korean-style packaging.
If it were you
One-line verdict: This is a sample of "a proven public template × a small-language market." Worth studying the playbook, not worth chasing this app specifically.
Why it's not worth much: GoTall's revenue has been widely reported, and from 9 to October a wave of copycats appeared across countries at once. The Korean slot alone already has three or four clones. Sumki itself reached #43 in its category, and monthly revenue is still only in the low thousands of dollars. A 1.6 star rating and a "everything costs money" reputation, combined with "predicted result + hard paywall," may invite review and refund problems (unverified). The ceiling is low.
Who it suits: People who already have a quiz + paywall + TikTok paid-acquisition pipeline, who want to add another language store. The marginal cost is very low.
Who it doesn't suit: First-time subscription app builders hoping to make a living from this one product.
If you still want to do it:
- Pick a market with a low bar for Top Grossing, where the English original hasn't been localized, and where there are existing local anxiety keywords. First check how GoTall and Taller rank in the Health & Fitness Top Grossing chart of that country's App Store. You need to be ranked 100 or lower for there to be an opening. Stores like Turkey, Indonesia, and Thailand, where Sumki translated but has 0 ratings, either weren't advertised or advertised without converting. You'll have to test them yourself.
- Write copy using local phrasing for anxiety. Don't translate "Height Predictor" literally. In Korea it's "숨은 키 / 성장판 / 골든타임" (hidden height / growth plate / golden time). For other countries, go look at how clinic and supplement ads talk on local TikTok.
- Don't copy its "completely free-less" approach. Learn from GoTall: keep some features free and take fewer 1-star hits.
- Acquire users through TikTok: run paid ads, or post a batch of "my dad is 175, my mom is 160, how tall will I grow"-style content every day. UPARO's approach is to give creators discount codes.
When the window is: This kind of template window is measured in months. GoTall's coverage ran from 8 to September, and copycats in each country started appearing 9 to October. Wait another quarter and most larger languages will already have someone in them.
What would show I'm wrong: If Sumki holds in the top 50 of Korea's category Top Grossing chart over the next month with its ratings rising, or if Appfigures' estimate climbs above $10K/month, then the revenue pool for a single small-language app is bigger than estimated here, and it's worth building one seriously.
Research notes: competitor table, acquisition evidence, full research report
- Competitors
Name Where Launched Scale How it differs from this one GoTall - Height Predictor iOS 2025-06-25 6,784 US-store ratings; publicly reported $100K+/month, peak $147,787; Korea Top Grossing #180 Original template, mostly English; part of the features still work with the paywall closed. Sumki only localized to Korean, with a harder paywall. Taller - Maximize your height iOS 2024-10-18 17,383 US-store ratings, 1,888 in Vietnam; dozens of small countries have category chart rankings The category's biggest player; drives volume through a TikTok account matrix. Did not do Korean-style packaging. Grow — Height & Glow Up iOS 2025-07-29 1,795 US-store ratings Sells height and looks improvement bundled together TallUp AI iOS 2025-06-25 736 US-store ratings English version of the same template HeightMax iOS 2025-10-30 126 US-store ratings; Korea Top Grossing #166 Foreign developer that also changed the store name to Korean, but ranks below Sumki UPARO: Height & Posture iOS 2026-09-28 Rating 0; TikTok creator @steamz12 single video with discount code got 540K–1.43M views Newcomer in the same period, using English creator discount codes to acquire users 골연령: 뼈 나이 측정 & 키 예측 iOS 2026-09-17 Korea Top Grossing #122, rating 0 Switched to "bone age" framing; Korean-language copycat in the same period 아이키기록 iOS 2022-06-09 160 ratings, 4.69 stars; ₩7,700 one-time purchase; Korea Top Paid #4–41 Aimed at parents, tracks against official growth charts, one-time purchase. Sumki targets teens themselves, with a subscription. Online expected-height calculators (calculator.net, Korean growth clinic web pages) Web Already around — Free, gives only a single formula result, no check-ins and no subscription - Where users come from
- Verified TikTok: the only review title mentioning it was "틱톡보고까름" (saw it on TikTok, since deleted). The privacy label declares identifiers used for tracking (ad attribution). No official account or creator videos found; whether it's paid acquisition or a content account is unverified.
- Verified Store search / related recommendations: store names are stuffed with keywords like "키 성장 예측 / 습관"; in several storefronts' "You might also like" sections it appears alongside BeTaller, Grovii, and Grow Taller
- Inferred A concentrated push: Korea's free chart hourly peak reached #38 on 10-25, then dropped out of the top 100 (agentic30). The shape looks like a paid push or a video going viral.
Sumki: the Korean height-prediction app, and how it squeezed into Korea's Health & Fitness Top Grossing chart
Research day 2026-11-06. Sources: our appstore database (agent-im machine, from 2026-10-28), Apple lookup / App Store pages, Google Play pages, Appfigures public pages, agentic30.app, public articles from onbo-hub / Starter Story, and TikTok search via TikHub. Anything not verified is marked "inferred" or "unverified."
Bottom line
Sumki copies almost exactly the playbook of the US app GoTall (a height-prediction app built by an NYU student aged 20; in 2026, 8–September, Starter Story and others reported it at "$100K a month"): long quiz → show "potential height" → hard paywall subscription + habit check-ins, translated into Korean. A Korean indie developer launched it two weeks after GoTall went viral. It got into Korea's Health & Fitness Top Grossing chart at #43 (2026-11-06) for two reasons: the Top Grossing bar in that category is low, and the English original wasn't localized for Korea (GoTall ranks only #180 in Korea's Top Grossing). Third, TikTok brought a small number of teen users with high willingness to pay. The real scale is small: Appfigures estimates fewer than 2026K global downloads and under $5K in after-tax revenue in 5 through October, with 7 ratings in total and an average of 1.6 stars. To be precise, this is "a proven template + small-language localization" just emerging in Korea. It hasn't "broken out" yet.
1. What the product is
- Name: 숨키 (Sumki) - 키 성장 예측 & 습관; the US store lists it as Sumki - Height & Habit Tracker, the Japan store as Sumki - 身長予測＆習慣トラッカー. Developer: Remaster Archive (리마스터아카이브). The store page and Google Play page list a sole proprietor in Pyeongtaek, Gyeonggi-do, Korea, with business registration number 409-25-44474. The official site remasterarchive.com also lists LARTH, a fitness and diet check-in app. iOS launch 2026-09-11, version 1.0.0 (9/12) → 1.1.4 (11/2). Sources: Apple lookup; App Store kr page; Play page; remasterarchive.com.
- How it works: enter parents' heights, age, weight, whether you've had growing pains → it calculates your "maximum potential height" → a "growth plate closing countdown" creates urgency → daily check-ins for early sleep, drinking milk, stretching, and posture → the "potential height" number changes in real time with check-in completion. (Play page original: "도파민 넘치는 쾌감", meaning "a dopamine-filled rush.")
- Pricing: subscription only, no free model. Weekly ₩5,500, monthly ₩19,000, yearly ₩29,000 ("In-app purchases" section of the App Store kr page). In replies to reviews, the developer confirmed the free part only goes as far as seeing your maximum potential height.
- Localized into 12 languages (Korean, English, Japanese, Traditional Chinese, Vietnamese, Thai, Indonesian, Malay, Hindi, Turkish, Portuguese, Spanish). But the all-storefront lookup shows only the Korean store has ratings (7), while the US and Japan stores show 0. Source: Apple lookup, 2026-11-06.
- The Android version is also live (com.remasterarchive.sumki). The Google Play Korea listing shows "1천+ 다운로드" (1,000K+ downloads), last updated 2026-11-02. Source: Play page. So the recall card's claim that "Android isn't out yet" is wrong.
2. Growth data
| Metric | Value | Source |
|---|---|---|
| Korea Health & Fitness Top Grossing | 2026-10-28 #102 → 11-01 #85 → 11-02 #72 → 11-05 #139 → 11-06 #43 | appstore library, chart_rank |
| Korea Health & Fitness Top Free chart | Between 10-28 and 11-06, it ranged #110–#194; third-party hourly data shows its best on 10-25 reached #38 | appstore database; agentic30.app |
| Total ratings | 10-28 6 ratings → 11-04 7 ratings (only 1 more in 7 days), average 1.57 | appstore library app_day; Apple lookup |
| Estimated downloads / revenue | 2026 through October, global downloads under 5K, after-tax revenue under $5K | Appfigures public page |
| Countries charted | Only 1 in Korea | Data card |
How to read these numbers: the Top Grossing rank keeps bouncing between #43 and #139, while the Top Free rank sits past 100. That means few downloads, but a high share of those downloaders pay, and each paying user spends more. 11-06 hitting #43 is a single-day peak, not a stable rank. On the same day, the apps right around it were StepsApp (22,295 ratings) and Leap Health's home workouts (4,904 ratings). In other words, on the Korean Health & Fitness Top Grossing chart, a few dozen subscriptions a day is enough to crack the top 50 (inferred).
3. Competitors
| Competitors | Platform | Launched | Scale (2026-11-06) | How Sumki differs |
|---|---|---|---|---|
| GoTall - Height Predictor(Grow Labs LLC,Michael Que) | iOS / Android | 2025-06-25 | 6,784 US-store ratings at 4.6 stars; publicly reported $100K+/month, peak single month $147,787 (onbo-hub 2026-08-27; Starter Story 2026-09-02); Korea Top Grossing #180 | The original playbook: a 47-screen quiz, paywall reach of 91%, 10 TikTok videos a day. Mostly English, not localized for Korea. Sumki's structure largely copies it. |
| Taller - Maximize your height(Virtual Network SA / Romandie) | iOS | 2024-10-18 | 17,383 US-store ratings and 1,888 in Vietnam; it's on the category charts of dozens of small countries | The category's biggest player. TikTok has plenty of "Replying to… use the Taller app"-style account-matrix videos (@cynuinfo, @cynuspeaks). |
| Grow — Height & Glow Up(Vincent, Enzo MARRA) | iOS | 2025-07-29 | 1,795 US-store ratings | Sells height bundled with "glow up" looks improvement |
| TallUp AI(Maria Josee) | iOS | 2025-06-25 | 736 US-store ratings | Leads with AI height boost, same template |
| HeightMax(HireThomas, Inc.) | iOS | 2025-10-30 | US store 126 items; Korean store name changed to 「키 예측·키 성장 관리 앱」, Korean Top Grossing #166,8 items rated | A few foreign look-alikes also used Korean store names, but rank far behind Sumki |
| UPARO: Height & Posture(Philipp Brockhausen) | iOS | 2026-09-28 | Rating 0; TikTok creator @steamz12 single video with discount code got 540K–1.43M views (2026-10) | A newcomer in the same period as Sumki, acquiring users through creator discount codes |
| BeTaller (Quang Nguyen, Vietnam) / Height Predictor AI – TallPath (Redoubt ApS) / 골연령 (Dajax LLC, Korea Top Grossing #122) | iOS | 2026-08 through October | still tiny | copycats that popped up across smaller-language markets at the same time; 골연령 (bone age) rendered with the Chinese term 骨龄 (bone age) |
| 아이키기록(Rich Soft) | iOS / Android | 2022-06-09 | 160 reviews, 4.69 stars, ₩7,700 one-time purchase, Korea Top Paid #4–#41 | a Korean veteran aimed at parents tracking their child's growth curve (per the KDCA growth charts); Sumki targets teens themselves and charges a subscription |
| Kidy, 키 성장 AI 코치 (LEAN ASIA), Grovii, etc. | iOS | 2026 years | every one has single-digit reviews | a cluster of small apps that appear together in the Korea store's 'You might also like' section |
| web calculators (calculator.net, and the 예상키 계산기 tools from Korean growth clinics such as 하이키한의원 and 키네스) | Web | Already around | — | free, returns a result from a formula; no daily check-ins, no subscription |
Verdict: this niche has lots of competitors and public templates. Sumki's difference isn't features. It's Korean-language packaging and Korean cultural framing: the phrase 숨은 키 (hidden height), a 성장판 (growth plate) countdown, and pricing in won. In the Korea store it ranks above every English original.
4. Where users come from
- TikTok (confirmed; likely paid ads or anonymous content accounts): the only App Store review is titled 틱톡보고까름 (saw it on TikTok, deleted). 2026-10-03,1 stars, 99 Days Survival. The App Privacy label declares data used to track you: identifiers, which suggests ad attribution (inferred: it's probably buying traffic). Searches on TikHub for 숨키, sumki, 잠재키 and 키 성장 앱 found no official account and no creator videos. Our TikTok Ad Library only covers ads served in Europe, and Meta's ad library has nothing for it. So whether it's paid ads or anonymous accounts posting creatives is unverified.
- Store search and related-app recommendations: in the 'You might also like' sections for the Korea, Canada, Indonesia, and Chile stores, it appears alongside BeTaller, Grovii, and Grow Taller (App Store related-apps pages). The store name packs in the keywords 키 성장 예측 (height growth prediction) and 습관 (habit).
- Brief free-chart spike: third-party hourly data shows 10-25 it peaked at #38 on the Korea Health & Fitness free chart before dropping out of the top 100 (agentic30). The shape matches a burst of paid spend or a viral video (inferred).
- Channels not seen: no press coverage, nothing in our X corpus, no Korean blog mentions, and no official TikTok account.
5. Why it charts
- Copying a proven, publicly documented template, with tight timing: breakdowns of GoTall reaching $100k/month spread through 2026-08-27 (onbo-hub) and 2026-09-02 (Starter Story's TikTok), and Sumki launched 2026-09-11 afterward. Both the features (parent height → predicted adult height → sleep, nutrition, stretching, and posture check-ins that change the number) and the monetization (free results, everything else behind a hard paywall) match (inferred: it was built after reading the coverage).
- The Korean category's top-grossing bar is low, and the English originals never locked it in: the Korea Health & Fitness Top Grossing chart sits around #40, dominated by mid-sized older apps. GoTall ranks #180 in Korea and HeightMax #166. A Korean-native version priced in won can outrank them without much revenue (appstore library, 2026-11-06).
- Korean teens and parents care intensely about height, so the cultural fit is natural: phrases like 성장판 닫히기 전 (before growth plates close) and 골든타임 (golden window) are common on Korean TikTok in content from growth clinics and supplement sellers (a TikHub search for 성장판 닫히기 전 returns many clinic and sales videos). Sumki builds this anxiety narrative directly into the app copy.
- The hard paywall makes each paying user worth a lot: the free chart stays beyond 100 places, while the top-grossing chart reaches the top 50. The weekly price of ₩5,500 is below the price reported for the US original, which lowers the barrier for impulse purchases by teens (inferred).
6. Differentiation
- Compared with English originals like GoTall and Taller: there's almost no functional difference. The only differences are Korean localization and Korean-style anxiety framing (숨은 키, the growth plate countdown, won pricing), plus a harsher paywall: GoTall still offers some features after you dismiss the paywall, while Sumki has no free mode at all. Localization is why it outranks the originals in Korea, but there's no technical or data moat, and anyone can copy it (HeightMax has already added a Korean store name).
- Compared with the Korean-native app 아이키기록: the target users differ. 아이키기록 is for parents, tracks against official growth charts, and sells as a one-time purchase. Sumki is for teens themselves, sells the motivation and habit of 'growing taller,' and charges a subscription.
- The cost: 1.6 stars, with users complaining that 'everything costs money.' That reputation drags down store conversion and adds refund and review risk (App Store guidelines on 'predictive results + hard paywall' are tightening, unverified).
7. How many people know about it / is anyone copying it
- How many people know about it: very few. No revenue has been disclosed, no press coverage, no discussion on X, and no Korean blog posts. Only auto-scraped data sites like agentic30.app index its pages. But the template it copies (GoTall) has been widely covered, so the opportunity is already crowded; only the 'Korean version' slot is still empty.
- Copycats: in the Korea store, around the same time, 골연령 (Dajax LLC, 2026-09-17, top grossing #122) and 키 예측 AI - 톨패스 (Redoubt ApS, 2026-08-21) appeared, and HeightMax added a Korean store name. In Vietnam there's BeTaller (2026-10-01). These look more like GoTall being copied in many countries at once than like anyone copying Sumki specifically.
8. What others can borrow
- The arbitrage of 'proven template × language market': take an English hard-paywall app that has publicly reported revenue and build a native-language version tuned to local anxieties in markets like Korea, Japan, Vietnam, or Turkey, where the top-grossing bar is low and the English original was never localized. With little spend, it can reach the top 50 of the top-grossing chart.
- Copy rewrite: take a generic 'predict your height' pitch and rephrase it with anxiety terms locals instantly recognize (in Korea: 숨은 키 / 성장판 / 골든타임).
- Risk: giving no free features at all invites 1-star reviews. Following GoTall and keeping some features free after the paywall would improve reputation.
9. Still unclear
- Whether the TikTok push is paid ads, its own anonymous content accounts, or creators: I found no specific creatives.
- Actual revenue: Appfigures only gives a range of <$5K/month; whether 11-06's #43 holds up needs another week of data.
- Why the other 11 language stores have no reviews: not yet promoted, or promoted without converting?
- Android 1,000+ installs revenue, and its Google Play Korea ranking (our googleplay library doesn't cover it).
Sources
- App Store kr page: apps.apple.com/kr/app/id6803796187 (price, reviews, developer replies, privacy labels, related apps)
- Apple lookup: itunes.apple.com/lookup?id=6803796187&country=kr / us / jp
- Google Play:play.google.com/store/apps/details?id=com.remasterarchive.su…
- Developer website: remasterarchive.com/
- Appfigures: app.appfigures.com/reports/app-profile/338673465969 (2026 year, October downloads <5K, revenue <$5K)
- agentic30: agentic30.app/data/apple-6803796187 (hourly Korea free-chart rankings)
- GoTall breakdowns: onbo-hub.com/newsletter/this-20-year-old-grew-a-height-predi… (2026-08-27); Starter Story TikTok www.tiktok.com/@starterstory/photo/7680973978927648014 (2026-09-02)
- appstore library: chart_rank, app_day, app_profile (kr, 2026-10-28 to 11-06)
- TikHub TikTok searches: 키 예측 앱, 키 성장 앱, 성장판 닫히기 전 (2026-11-06)