"A Plush-Only SNS": a programmer built it in one month with Claude Code, growing from 1,500 to 30k users in two or three days
What it is A social app where you can only post photos of plush toys: each toy gets its own profile, you can "pet" other people's toys through the screen, and there are no comparison features.
Why it took off Japanese plush-toy fans could only post on X/IG via secondary accounts, afraid of being watched and compared. "Only plushies, super peaceful, you can pet them" is a one-line pitch, and one recommendation post brought in nearly 30k users over two or three days; after adding Traditional Chinese, Taiwan's Threads sparked a second wave.
CHow you could follow Don't copy the Japanese plush SNS outright; borrow its playbook for a different audience: buy ads to collect pre-registrations, then offer a small community of people who post on general SNS through secondary accounts a place that is "only fellow fans, no comparison," plus an emotional action and a milestone number that can be screenshotted.
- Data (updated daily) · first launch 2026-09-12 · 11-07 installs 23,340
Android · Total installs worldwide Data 2026-10-29 → 2026-11-07 (10 days, 10 observations). Google's detail page only refreshes install counts every other day, so a flat day doesn't mean nobody installed.
Japanese programmer Shin built a social app that only allows posting photos of plush toys, "ぬい日和" (Nui Biyori). It launched in June, got pushed into a boom by an ordinary user's recommendation post in late July, sparked a second wave in Taiwan after adding Traditional Chinese in October, and reached about 95k users by November. It took off because it served a group that had long existed without a dedicated place, plus a simple action people could screenshot. Below: how it got started, where the money comes from, who is copying it, and whether you should follow.
A recommendation post that looked like an ad
On Jul 21, 2026 at 4:13 p.m., X user けーる (@Mamecha_isBeans) posted:
みんな聞いて…神アプリ見つけちゃった…ぬい日和っていうアプリなんだけど、ぬい専門のSNSで、余計な投稿がなくて超平和…… (Everyone listen… I found a divine app… It's called ぬい日和, a plush-only SNS with no unnecessary posts, super peaceful……)
She went on to list three things: each plush can be registered as an "うちの子" (my kid) with its own profile; you can log how many days you've been together and manage the plush's outfits; and finally "みんなのぬいをナデナデできる," you can pet other people's plushies too.
That same night someone replied, "the writing style looks like an ad," and she answered, "Y-yeah, you're right…" The exchange was compiled on posfie (7-22). The developer himself reposted it with "このアプリです👀(とても嬉しい)" (This is the app 👀 (so happy)).
According to the developer in an ITmedia interview (8-03), he had posted the day before celebrating users passing 1,500; within two or three days it passed 30k, and by Jul 29 it was about 40k. There is no evidence this post was paid for; "looks like an ad" was just netizens' impression.
What it is
A photo SNS where only plush toys can be posted. In Japan, taking plush toys out, photographing them and changing their outfits is called "ぬい活," and these fans used to post on X and Instagram through secondary accounts.
A few key design choices:
- Each plush has its own profile: registration shows a "◯◯日いっしょ" (together for ◯◯ days) counter; a "wardrobe" records outfits worn.
- なでなで (petting): tap the hand icon at the top right of a photo to pet that plush through the screen; the owner gets a notification, and you can set each plush's "where it likes being petted."
- Deliberately no comparison: pet counts are hidden from others, like counts can be hidden, and there are no reposts, videos or rankings. The developer's explanation to ITmedia: "Otherwise people would feel sad thinking their kid gets petted less than others."
The developer Shin is a Japanese programming YouTuber (about 137k subscribers). The idea came from his wife: she already takes her plush toys out to photograph them, and said she worried about being "looked at strangely" posting them on general SNS, and kept scrolling into unrelated negativity. Shin spent about a month alone building the first version with Claude Code; the iOS version launched in Jun 17 and the Android version in Sep 12.
Why this one took off
The category isn't new. Japan's long-running "ふわもこSNS" launched 2019 years ago, and in the first half of 2026 a batch of ぬい活 logging apps also appeared; none took off. ぬい日和 won on three fronts:
It can be explained in one line. "Only plush toys, super peaceful" is itself made to be shared on X. けーる's post simply repeats it.
It has something screenshottable. Petting is an action anyone understands at a glance; "days together" is a number. The developer said posts started appearing on X like "after registering I found out I've known this kid for 1000 days" and "turns out we've been together 1555 days." Every screenshot brings in new users.
It protected the atmosphere. The no-comparison design attracts exactly the people worn out by SNS comparison. During the surge, veteran users welcomed newcomers on their own, and the developer reviewed reports one by one himself.
The rating counts on the Japan App Store show the gap: ぬい日和 collected 3,050 ratings in 4 months and a half, while ふわもこSNS, which had been running for 7 years, has 2,953 (iTunes, 11-06).
Where users come from
Buy ads first, confirm demand, then write code. ITmedia reported that after finishing the first version he first ran a pre-registration beta, then "resumed buying ads" once things were stable, and the boom came a month later. The developer has two lessons in his paid course, "validating demand with ads" and "calculating CPA"; by his own account, after getting the idea he first made mockups with AI and bought ads on X and Instagram to collect pre-registrations, getting thirty to forty a day, and that's when he decided to build it (couldn't find the original source for this number; unverified).
Spread inside the Nuiikatsu circle. The first wave was casual user recommendation posts around Jul 21, followed by Togetter (7-24, "An AI-built ぬい活 SNS passes 20k in one month"), ITmedia, tutorial sites and YouTube reviews. The developer's own followers are programmers, not people from the plush-doll scene. His reputation mainly carried the "one person, built with AI, became a hit" story across developer circles.
Adding Traditional Chinese sparked a second wave on Taiwan's Threads. In late October it added English, Korean and Traditional Chinese; on Oct 23 the official account posted that "overseas users surged today." Many people pushed it on Taiwan's Threads, and some wrongly promoted it as "you can post selfies and idol photos," so real-person photos briefly flooded the feed, and the official side changed the posting rules the next day. It reached #14 on the iOS Taiwan social free chart (10-28), and #6 on the Google Play Taiwan social free chart and #56 overall free (10-29).
The Android version absorbed pent-up demand. When it blew up in July, many people asked on X why they couldn't find it on Google Play. Installs on Google Play reached 6 by Nov 23,340, with a jump of 1 on Nov 5,363, which matches the Taiwan wave.
Channels not found: searching "ぬい日和" on TikTok turns up no relevant videos; Reddit has only one post.
Heat is fading: by Nov 6, the Play Taiwan social chart had slid to #78 and Japan to #129; iOS Taiwan and Hong Kong have been sliding too.
Where the money comes from: still losing money
- A ¥300/month 応援プラン (supporter plan), plus tips, background themes, and supporter badges; in-app prices on Google Play run $1.89–64.99.
- No ads, no cap on the number of plushies, no cap on images per post. The developer says limiting the count would "definitely make more money," but "people came here in the first place, and it would hurt them to be stopped from registering more plushies."
- The result: at the end of July he said it was still losing money (ITmedia). By November, his bio on X put monthly server costs at over ¥200k. He has said that if it comes to it, he'd look for plush-related merchants to advertise with. A longer-term idea is a marketplace for plush and doll-outfit makers (inferred from his public letter in September; not found in the original text).
It can reach around #145 on the Google Play Japan social top grossing chart, so some people are clearly paying, but it is still far from breaking even. The actual revenue figures have not been disclosed.
Who it's competing with
| Product | Launched | Scale | How it differs from ぬい日和 |
|---|---|---|---|
| ふわもこSNS | 2019-07 | App Store Japan rating 2,953; Taiwan has a Traditional Chinese version | The plushies themselves post, leaning toward roleplay, with a high barrier to entry and flat growth |
| 娃寶日記 NuiDiary (Taiwan) | 2026-04 | single-digit ratings | A private diary shared only with invited friends. Some in Taiwan accused ぬい日和 of copying its UI, and ぬい日和 is adding a "petting" feature |
| ここもこ | 2026-04 | Ratings 9 | Chatting with your plushies, AR, photo albums; a solo log, not a community |
| ぬいろぐ, ぬいログ, ぬいちゃっと, Nuikoyomi, and others | After 2026-07 | Ratings 0~7 | Copycats that appeared after the boom. Nuikoyomi's slogan nearly copies "no following, no liking, no comparing," and none of them have gained traction |
| Plushie alt accounts on X / Instagram | — | The original main stage of ぬい活 | Passersby, negative messages, and number comparisons, the very things ぬい日和 is selling itself as the opposite of |
Anyone can copy the features, and some have, but none of the copycats took off. The early product took the community atmosphere and the user base, and later entrants with the same features couldn't get people to switch.
If it were you
Bottom line: C. Building a Japanese plushie SNS now makes no sense; it's already been built, and translating it has been done too. What's worth learning is its playbook, which you can run again on a different audience.
It took off because of three things: a group who had long had alt accounts on mainstream SNS and feared being seen; a positioning you can explain in one sentence; and actions and numbers people can screenshot. All three can be copied, but social products have a cold-start problem, need community management, and still lose money at scale. ぬい日和 has 95k users and is still losing money. So treat it as a method, not a business to copy directly.
Good fit for: developers who are already inside a niche (or have people around them who are), who understand what that group is afraid of; people willing to spend small amounts on X / Instagram ads and collect pre-registrations before writing code; people who can personally review reports and reply to users every day.
Not a fit for: anyone wanting to build a Japanese or Traditional Chinese plushie SNS (ぬい日和 already holds that spot, and copycats have gotten no traction); anyone counting on quick profits (supporter-style payments don't cover server costs, and it's losing money itself); anyone without a niche who just wants to "find a vertical and build an SNS."
How to do it: pick an audience with high identity that posts from alt accounts on mainstream SNS: cotton dolls, goods collectors, bullet journaling, succulents, leopard geckos, vintage cameras... First confirm there's no decent dedicated community for it in your language. Use AI to draft a few mockups, run ads for one or two weeks to collect pre-registrations, and work out what each registration costs you. Build the minimum version: one profile per "main character," one emotional action that's screenshot-worthy, one commemorative number that's screenshot-worthy, and no rankings or public counters.
How to get users: don't count on your own following. Find people in the niche willing to beta test, write your positioning as one sentence people can repeat, and wait for insiders to post "I found an amazing app" themselves. For niches with lots of creators, don't use AI-generated promo images: ぬい日和 got flamed for AI icons in late July, and within a day it apologized publicly and switched to photos of real objects. When you launch in a new language, launch the posting rules with it.
Is there a window before this: no clear window. The ぬい活 wave is still going in Japan, and Taiwan's second wave is already fading. If you build for a different audience, you're not in a rush, but you are racing to claim that audience before someone else does.
What would show you read this wrong: ① ぬい日和 publicly breaks even or starts earning in the first half of 2027 (for example, by launching a creator marketplace). That would show this kind of community can make money, and following it would be worth more than a C. ② The reverse: if it shuts down or charges a lot more, that shows this path can't sustain even the people who make it work. ③ A similar product in a different niche (say, cotton dolls or pets) using the same playbook passes 10,000 downloads within a month. That would show the method transfers, and it's worth moving fast on.
Sources
- ITmedia NEWS interview (2026-08-03): www.itmedia.co.jp/news/article/2608/03/2000000358/
- posfie roundup (7-22, first-wave recommendation posts and replies calling them "ads"): posfie.com/@petaritape/p/wmXk3or
- togetter(7-24):togetter.com/li/2724140
- Developer's X (user count, monthly server costs): x.com/Shin_Engineer; official X 10-23 overseas user announcement
- Google Play installs and rankings (10-29 to 11-06); App Store ratings and rankings by store (10-28 to 11-06); iTunes lookup (11-06)
- Taiwan controversy: Threads (10-28), Plurk
- Anything marked "inferred" or "unverified" is an inference or unconfirmed.
Research notes: competitor table, acquisition evidence, full research report
- Competitors
Name Where Launched Scale How it differs from this one ふわもこSNS / 芙娃萌可社群 iOS 2019-07 Japan rating 2,953, claims 500k posts in total ふわもこ has plushies post as characters themselves, leaning toward roleplay, older, with flat growth. ぬい日和 centers each profile on the owner, uses an IG-style layout, and adds "nadenade" petting and a no-comparison design. nuidol iOS 2019-03 Rated 59,2023, no updates since A manufacturer-made ぬい撮り community that no one maintains anymore ここもこ(REVCREATE) iOS 2026-04 Ratings 9 Chatting with plushies, AR, photo albums; a solo log, not a public community 娃寶日記 NuiDiary iOS 2026-04 Taiwan rating 4, Japan 7 A private photo diary shared only among invited friends; Taiwanese circles accuse ぬい日和 of copying its UI ぬい日記 / NuiDays / ぬいまっぷ and other personal tools iOS 2025-10 to 2026-07 Ratings 0~7 Logging and map tools with no community and no sharing hook ぬい垢 (plushie alt accounts) on X / Instagram Big-company features — The original main stage of ぬい活 Mainstream platforms have passersby, negative messages, and number comparisons; ぬい日和 sells "plushies only" - Where users come from
- Verified X / Instagram ads (demand validation, then scaling after beta): ITmedia: the day after the idea, it ran X/IG ads to collect pre-registrations, 30–40 per day; ads resumed after beta; the paid course has a lesson on "CPA calculation."
- Verified Recommendation posts from ordinary X users: 7/21 @Mamecha_isBeans's "神アプリ見つけちゃった" drove the first wave; 1,500 users the day before, and it passed 30k within 2–3 days (ITmedia, posfie)
- Verified Media and roundup sites: togetter 7/24, posfie 7/22, ITmedia 8/03, did2memo tutorial, YouTube reviews
- Inferred The developer's personal brand (a YouTuber with 137k subscribers): @Shin_Engineer reposted the first-wave recommendation post and packaged the app into a paid course, "Claude Code 個人開発スタートアップの教科書"; the direct effect on acquisition in the ぬい活 community is unverified
- Verified Organic spread on Taiwan Threads after localization: Traditional Chinese, English, and Korean were added in late October; the official 10/23 announcement says overseas users surged; Plurk says "lots of people are promoting it"; Play Taiwan SOCIAL #6 (10/29)
- Verified The Android version met a backlog of demand: in July many people on X said they couldn't find it on Play; the 9/12 Android version launched
- Inferred TikTok: a TikHub search for "ぬい日和" returns no related videos
ぬい日和 Nui Biyori (com.nuibiyori.app): why it took off
In one line: Shin (@Shin_Engineer), a Japanese YouTuber and indie developer with 137k subscribers who makes programming videos, built a "social network for plushies only" in one month using Claude Code. It first ran ads on X/Instagram to validate demand. About a month after launch, an ordinary user's "神アプリ見つけちゃった" recommendation post on X sparked the Japanese ぬい活 community, and it went from 1,500 to 30k users in 2–3 days. In late October, after adding Traditional Chinese, English, and Korean, Taiwan's Threads drove a second wave. As of 2026-11, it had about 95k users (per the developer's X bio). The Play version is just the Android tail of this traffic.
0. Data card and figures from the library
| Metric | Value | Source |
|---|---|---|
| Play installs | 23,340 (2026-11-06), 7 day +6,502; 11-01 saw a one-day jump of +5,363 (Play install bands updated, reflecting the Taiwan wave in late October) | googleplay library app_day |
| Listed on Play | 2026-09-12 (Android launch; iOS came much earlier, in 2026-06-17) | Data card / ITmedia |
| Play ranking peaks | 10-29 Taiwan SOCIAL free chart #6, Taiwan all-apps free chart #56; Hong Kong SOCIAL #15; Japan SOCIAL free #79, Japan SOCIAL grossing #145; by 11-06 it had dropped to Taiwan #78 and Japan #129 | googleplay library chart_rank |
| iOS ratings | Japan store 3,050 (11-06,7 day +71), Taiwan store 265 (7 day +31), Hong Kong store 29, Korea store 14, US store 9; average 4.83–4.93 | appstore library app_day / iTunes lookup |
| iOS ranking | 10-28 Taiwan-region social, free: #14; Hong Kong #26; Macau #33; Japan #132→#153. Taiwan and HK have been sliding steadily since then. | appstore library app_day |
| total users | 6/17 launch → around 7/20 1,500 → 7/23 20k → 7/29 about 40k → 9/29 about 60k → November 95k | Developer's X bio, ITmedia, togetter |
| Monetization | Monthly ¥300 応援プラン (support plan) + tips / themes; Play in-app purchases $1.89–64.99; no ads, no cap on うちの子 (plush profiles). Still losing money: monthly server costs exceed ¥200k. | ITmedia; @Shin_Engineer's X |
For comparison: Japan's long-running similar app ふわもこSNS has been around for 7 years with a Japan-store rating of 2,953. ぬい日和 reached 3,053 in 4.5 months and has already passed it (iTunes lookup, 2026-11-06).
1. Competitors: who else does the same thing
| Product | Where | Launched | Scale | How it differs from ぬい日和 |
|---|---|---|---|---|
| ふわもこSNS(Daiki Shimizu / tsukuricom) | iOS + Android | 2019-07 | Japan-store rating 2,953; claims 7 years and 500k cumulative plush memories. Taiwan has a Traditional Chinese version, 芙娃萌可社群 (Taiwan-store rating 45). | The 'plush posts for itself' persona: old, niche, slow growth. ぬい日和 instead has the owner create a profile for each plush (welcome day, wardrobe, なでなで), with an IG-like interface and a 'no comparison' design. |
| nuidol (SEKIGUCHI, maker of Monchichi) | iOS | 2019-03 | Score 59,2023 — no updates in years | Maker-built ぬい撮り community, now no longer updated. |
| ここもこ(REVCREATE) | iOS + Android | 2026-04 | Ratings 9 | Focused on chatting with plush, AR, and photo albums; more of a solo log than an SNS. |
| 娃寶日記 / NuiDiary (Taiwan, Chi-Lun Huang) | iOS + Android | 2026-04-02 | Taiwan rating 4, Japan 7 | Private photo diary, shared only with invited friends. Taiwanese circles accused ぬい日和 of copying its setup and UI. Its own site says 1.8.0 will add なでなで, so it is moving toward ぬい日和's direction. |
| ぬい日記 / NuiDays / ぬいまっぷ / ぬいろぐ / ぬいログ / ぬいちゃっと etc. | iOS | 2025-10 to 2026-11 | Ratings only 0~7. | Solo-developer logging, map, and chat tools; none took off. |
| ILCA きゅるちゃんぬいかつ, でぃあすてぬいかつ | iOS | 2025–2026 | Ratings 57 / 9. | An IP holder's AR camera, not a community. |
| ぬい垢 (accounts dedicated to plush) on X / Instagram. | Big-company features | — | The original main channel for ぬい活 users. | Not a dedicated space: passersby watch, negative content shows up, and numbers get compared. ぬい日和's selling point is precisely 'only plush.' |
Bottom line: this niche is not empty. The veteran ふわもこSNS has run for 7 years, and in the first half of 2026 a batch of ぬい活 logging apps arrived, but none broke out. ぬい日和 didn't win by being first.
2. Growth levers: where users come from
- Validated demand with ads first (confirmed, per the developer): the day he had the idea, he made a finished mockup with GPT Image, then ran ads on X and Instagram to collect pre-registrations. He got 30~40 sign-ups in one day and decided it would work. Ads resumed after the closed beta, and growth took off about a month later. (ITmedia 2026-08-03; his paid course lessons 6 and 7 are on 'validating demand with ads' and 'CPA calculation.')
- A regular user's recommendation post on X sparked it (confirmed): 2026-07-21 user けーる (@Mamecha_isBeans) posted "みんな聞いて…神アプリ見つけちゃった…" ("Everyone listen… I found an amazing app…"), praising it as "余計な投稿がなくて超平和" ("no extra posts, super peaceful"), "うちの子登録" ("registered my kid"), and "みんなのぬいをナデナデできる" ("you can pet everyone's plushies"). Someone replied that the writing style "文体が広告かと思った" ("read like an ad") (per a posfie roundup). ITmedia says the surge began with "多位用户的介绍帖" ("several users' recommendation posts"): the app had just celebrated 1,500 users the day before, then hit 30k within 2~3 days. The developer (137k followers) retweeted it with "このアプリです👀" ("this is the app 👀"). There is no evidence this was paid promotion; "looks like an ad" is just a netizen's impression and not proof.
- Amplified by media and aggregator sites (confirmed): togetter 7/24 'AI-made ぬい活 SNS reaches 20k users in one month,' posfie 7/22, an ITmedia NEWS 8/03 interview, tutorials on did2memo and app-liv, and YouTube review videos.
- The developer's own IP (partly confirmed): Shin is a programming YouTuber with 137k subscribers, and his X account has influence too. But his audience is programmers, not ぬい活 people. The first wave came from reposts within the ぬい community. His IP mainly helped spread the story of 'a successful solo-dev project,' which the developer community shared widely.
- Localization + second wave via Taiwan Threads (confirmed): 10/10 Taiwanese users kept asking for Traditional Chinese in the comments; around 10/24 the app added English, Korean, and Traditional Chinese in v1.5.x. 10/23 the official account posted that 'overseas users surged today.' On Taiwan's Threads (Plurk), many people promoted it, and some pushed the idea that you could post selfies and idol photos, which flooded the app with real-person photos (Plurk). The official team changed the posting rules in 10/24. In the same period, it ranked #14 on the iOS Taiwan social chart and #6 in Play Taiwan SOCIAL / #56 overall.
- The Android version unlocked suppressed demand (confirmed): when it surged in July, many Android users on X said they 'couldn't find it on Play.' The Android version launched in September, releasing the pent-up demand all at once.
- Store search and related recommendations (inferred): App Store 'customers also bought' lists link ふわもこSNS together with it; the name includes 'ぬい,' a high-frequency search term.
- Channels we did not find: searching 'ぬい日和' on TikTok returned no related videos (TikHub); our Meta ad library does not include it (the library only tracks products on its list, so a miss doesn't mean it didn't run ads); on Reddit, only one post in r/oshikatsu says 'now supports English.'
3. Why it took off
- The audience already existed; there just wasn't a dedicated place: ぬい活 (taking plush out, photographing them, changing outfits) has become a mainstream hobby in Japan. One claim says it was nominated for a 2025 buzzword award (YouTube video description, unverified). These people had long posted from alt accounts on X/IG, but worried that 'posting plush might look strange' and were bothered by negative content and number comparisons (ITmedia, quoting the developer's wife).
- A product you can explain in one line: 'a social network only for plush,' 'super peaceful, no extra posts.' That positioning is naturally shareable on X, and it was this one-liner that spread it in the first wave.
- Emotional features people want to share: なでなで (petting someone else's plush through the screen, with the owner able to set where it can be touched), 'days together' (days since welcome day), and wardrobes. Users screenshot and post these to X on their own, such as 'I didn't know we'd been together for 1,555 days,' and every screenshot brings in new users.
- Deliberately removing comparison: pets counts can't be seen by others, likes can be hidden, and there are no reposts or rankings. That appeals to people tired of SNS comparison and protects the community's atmosphere: during the surge, veteran users welcomed newcomers on their own (ITmedia).
- No paywalling features; monetize through support: there is no cap on plush count or photos. Only a ¥300/month support plan and tips are sold. 7/23 users said 'I subscribed to support you' (togetter). The Play version's Japan SOCIAL grossing chart reached #145~#162.
- The developer responds fast: he replies to users within 3 hours, updates often, and personally reviews reports. When an AI-generated icon controversy broke out, he posted a detailed apology and fixed it within a day. Trust in the community was built through these actions.
4. What's the differentiation, and is it why it broke out?
- Versus ふわもこSNS: ふわもこ lets 'plush post for themselves,' a roleplay-oriented style with a higher barrier to entry. ぬい日和 centers on the owner, giving each plush its own profile in a familiar IG-style layout, plus the distinctive なでなで interaction and the 'no comparison' rule. The core features are shared by everyone; what really differs is the gentle tone and the 'pet' action that is instantly screenshot-worthy.
- Versus logging apps (娃寶日記, ここもこ, etc.): they are private diaries or solo tools with no public timeline, so no network effect. ぬい日和 is a public community: the more content, the more people come.
- Was it the reason for the growth?: yes, but only half. Differentiation (only plush, なでなで, no comparison) made the post worth sharing. The other half was the developer's growth skill: validating with ads first, calculating CPA, scaling after the closed beta, plus the media story from his personal IP. Without either half, it probably wouldn't have taken off: other ぬい apps at the time had similar features, but nobody shared them, and their ratings stayed in single digits.
- Weak moat: the interface has been called a copy of IG / 娃寶日記, and the features are easy to copy; the copied side is already adding なでなで. What can really hold is the community atmosphere already built and the early user base.
5. How many people know about it, and is anyone copying it?
- Already widely discussed: ITmedia interview, togetter, posfie. The developer himself has publicly shared his growth tactics and costs on X, YouTube, and his paid course 'Claude Code 個人開発スタートアップの教科書' (23 course, covering demand validation, CPA, infrastructure costs, and handling controversy), including monthly server costs exceeding ¥200k. User numbers are public; revenue figures are not, but he admits it's still losing money. In Japan's indie dev circle, it's a 'textbook-level' public case, so it's not unknown.
- Copycats: appearing after 2026-07: ぬいろぐ (CapCat, 7/16, social categories), ぬいログ－うちの子と話そう (9/14), ぬいちゃっと (creem, 11/02), and Nuikoyomi on Play (with the pitch 'don't follow, don't like, don't compare,' nearly copied verbatim). None has traction yet; 娃寶日記 is also adding なでなで.
- Risks: Taiwanese circles are split over 'copying + AI promo images' (a Threads post with 44k views, 10/28); after overseas users arrived, post quality dropped and operating costs rose; rankings in Taiwan and Hong Kong are falling.
6. What others can learn
- Make a mockup first, run ads to collect pre-registrations, and use CPA to judge whether it's worth building. Start building once you get 30~40 sign-ups in a day. Build the MVP in a month with AI coding.
- Find high-identity audiences who already run alt accounts on mainstream SNS (plush, cotton dolls, pets, plants, planners…) and give them a dedicated place of 'only fellow fans, no comparison.' Spread it with a positioning you can explain in one line.
- Design an emotional action that's screenshot-worthy (petting) and a number that's screenshot-worthy (days together), so users post them to X and become the ad themselves.
- Support-style monetization: no feature paywall; sell supporter status and decoration to earn word of mouth and trust. The cost is that it's still losing money, so work out unit economics early.
- Pitfalls: for handmade and creator circles, don't use AI-generated promo images; roll out multiple languages together with the posting rules, or new users who don't know the rules will overwhelm the community.
7. Still unclear
- The scale and spend of cold-start ads, and whether anyone was asked to post before the initial surge, are unverified ('looks like an ad' is just netizen impression).
- It's unclear whether 95k is registered users or DAU; conversion rate and support-plan revenue are unknown. The data card mentions a '9/29 open letter' (contents: server costs not covered, considering ads with plush-related merchants, and a long-term EC platform for plush and outfit makers), but that comes from notes taken during retrieval, and I couldn't find the original text this time.
- The drop in Taiwan and Hong Kong has been fast, and how many users it can retain in the second wave is unknown; no sign yet of traction in Korea or English-speaking markets (Korea rating 14, US rating 9).
Sources
- ITmedia NEWS 2026-08-03 interview: www.itmedia.co.jp/news/article/2608/03/2000000358/ (incl. /2)
- togetter 2026-07-24:togetter.com/li/2724140
- posfie 2026-07-22 (roundup of first-wave recommendation posts): posfie.com/@petaritape/p/wmXk3or
- Official X 10/23 overseas users announcement: x.com/nuibiyori_x/status/2113609349310669159
- hashout.jp 10/24 posting rules revision: hashout.jp/sns/13138/
- Developer's X profile (95k users, monthly cost ¥200k): x.com/Shin_Engineer
- ShinCode Academy course catalog and the "flame war" lesson: shincode-academy.dev/courses/18a10c79-e6e3-4b8c-b0a8-9390335…
- Taiwan controversy on Threads (10/2.84M views): www.threads.com/@guiyuluobo.13/post/DfCqJbrCZ6t/ ; Plurk: www.plurk.com/p/3jb7pzknp9
- Nuidiary official site: nuidiary.com/zh/ ; ふわもこSNS: fuwamoko.app/ ; ここもこ: cocomoco.jp/
- Official site: www.nuibiyori.com/
- Sources: Google Play (app_day, chart_rank, 2026-10-29~11-06), App Store (app_day, app_profile, review, 2026-10-28~11-06); iTunes lookup (2026-11-06)