"14 degrees isn't called 14 degrees, it's called cardigan weather": an Instagram joke that became Turkey's #1 weather app in 12 days

In Oct 13, a Turkish designer posted a short Instagram video about a weather app that doesn't exist: it doesn't show degrees, it just tells you, like a mom would, to "bring a cardigan". The comments asked where to download it. 12 days later it really was on the App Store, and a week after that it had passed Windy, AccuWeather and the national weather service on Turkey's free weather chart. The feature isn't new; someone in the same country had built the same thing a month earlier and got only 9 ratings. The difference was everything that happened before launch.

A video saying it's "not real"

On Oct 13 in the afternoon, Selinay İblikci posted a Reel on her Instagram. She runs Puoi Studio, a small design studio in Amsterdam, and usually posts design content. The caption on that video read:

"14 degrees means nothing to me. But "bring the cardigan" is perfectly clear. …So I designed HIRKA, a weather app that talks in decisions you make before leaving the house, not in numbers. Tank top weather, cardigan weather, coat weather, and today don't go out. HIRKA is not a real app. Not yet."

The last line asks viewers: "What's the thing you hear most at home when you're about to go out?"

"Hırka" is the Turkish word for cardigan, and "hırka havası" (cardigan weather) is something nearly every Turk has heard from their mom. Puoi later wrote the story up as a case study: "People loved it and kept asking when they could download it… the comments turned into a waitlist."

The app launched on iOS on Oct 25, and on Android on 31. The caption on the same video was later changed to "I said 'not yet.' HIRKA is now on the App Store, link in bio." On Nov 2 she posted again: "I said HIRKA isn't real yet. I take it back." (Instagram post; the posting date is inferred from the post ID.)

What it actually is

A weather app whose home screen shows no temperature, just one sentence:

• Four levels, one sentence. It reads the feels-like temperature, wind and rain, then gives one of: "tank top / cardigan / coat / don't go out." The default cutoffs are about 10° and 16°, and you shift them up or down depending on whether you run cold and whether you walk or bike (hirka.app, 11-06).
• The mom voice runs through everything. Notifications read "It's getting cooler, did you bring a cardigan?" and "Don't go out with wet hair." Each evening at 21:30 there's one message: "Cardigan weather tomorrow, rain after 17, leave the umbrella by the door." Only one a day. For the first 15 days it asks every night "Did you dress right today?" and adjusts the threshold based on your answers. On the weekend it sends a "Mom's report card": "You listened on 7 of 5 days."
• Widgets, lock screen and Apple Watch. The case study says: "Most morning users never open the app. A line on the lock screen is enough."
• The paid tier sells your own wardrobe. You photograph your clothes and it picks one from your closet for the day's weather ("the burgundy wool cardigan, enough for morning and noon"). There are also layering plans and a travel packing list. HIRKA+ costs ₺399.99 a month or ₺999.99 a year (roughly $9/month, estimated), with a 7-day trial. The free tier stores only 3 garments. 11 languages.

Two people make it. Selinay handles product, brand and social accounts, and the developer account belongs to Ege Yildizli (the same account also has a trip planner and a small game app). The case study's own words: "A two-person product collaboration, no ad budget, no marketing team." How they split the work isn't visible from outside.

How fast it grew

(App Store charts and rating counts by store, 10-28 to 11-06; Turkey store average 4.78 stars)

11-06 Turkey Weather Top Free: it's #1, Windy is #2, the national met service's Hava Durumu is #4, and AccuWeather is #10. Azerbaijan (Turkic-speaking, watches Turkish content) has hit #1 several times, North Macedonia and Cyprus have made the top 10, and places with large Turkish communities like Germany, the Netherlands, Belgium and Austria have charted too. On Google Play it was released 10-29 and has 4,405 installs, ranking #3 in Turkey Weather Top Free.

Read these numbers at Turkey's scale. The weather category is small: a few dozen ratings can take the top spot, and the top spot itself brings organic traffic from the store. It has not charted on any grossing list, so how much it earns is not visible.

Where users come from

First, and most important: the founder's own Instagram. Post the concept video, watch the reaction, build it only if people respond, then go back to the same audience and say "it's live." On launch day the app didn't start from zero: it went to a group of people who had been waiting 12 days.

Second, a separate brand account, @hirka.app. It posts a daily city outfit card ("Istanbul: cardigan day today, bring an umbrella"), carousels, Q&A stories, and a faceless short-video series, "If HIRKA were a person," all voiced by the same AI narrator. It has been posting every day for 11-03 to 11-05 days.

Third, everything in the product is shareable. The report card, the evening check-in, and the mirror selfie turned into an outfit card for "sending to Mom" can all be shared to stories with one tap. The case study calls this "turning retention into distribution." How many users it actually brings in is not visible from outside.

Fourth, the store title rides a high-frequency search phrase. "Bugün ne giysem" (what should I wear today). The website also has guide pages like "what to wear at each temperature." Effect unknown.

Ads: none found. No related videos on TikTok, nobody mentions it on X, and the case study says plainly there was no ad budget. It reached #3 in Cyprus, and the case study specifically notes "zero local promotion."

Why this one

The same idea was done before it. Turkish developer Utku Barın's kuyara: What to Wear Today launched in Sep 15, same premise of "check the weather and tell me what to wear," and it still has only 9 ratings, peaking at #203 on the Turkey weather chart. From May to November, roughly 30 "weather-based outfit" apps appeared on the App Store, most with only 0–5 ratings. What HIRKA added:

1. Validate demand first, have the audience in place. The video itself said "not a real app," and the people asking to download in the comments were the first users.
2. A line everyone has heard. "Cardigan weather" needs no explanation, so a weather app suddenly became something you could forward as a joke. The feature is the tool; the persona is the thing people share.
3. Timing. Late October to early November is when Istanbul is cool in the mornings and evenings and warm at midday, so "cardigan weather" was right almost every day.
4. Built to be something you use every day. A Turkish user 11-04 wrote: "I'd used my phone's built-in weather for years. I got used to HIRKA in four or five days, and now I don't leave the house without checking it."

Its weak spots

• The feature has no moat. Outfit recommendations from weather have dozens of entrants this year, and the built-in weather app could add a "wear a coat" line any day.
• Money isn't proven yet. The free tier gives only 3 garments, and reviews already grumble: "It would be great without in-app purchases, otherwise you can only add 3 tops🥺" and "The only downside is some extra features cost money." About $9 a month is not cheap in Turkey, and it hasn't reached the grossing charts.
• The topic fades when the season ends. "Cardigan weather" is funny because the seasons keep changing day to day. In deep winter every day is "coat weather," and there's nothing left to say in one line. Some people also find the calls inaccurate: "This rating is way off, I froze to death" (one star, 11-01).
• The other 10 languages have barely moved. English, Japanese, Korean and Chinese versions exist, but only Turkey and Turkic-speaking places have gained traction. The persona is a Turkish mom, and it doesn't survive translation.

Who's competing

After HIRKA came WearCast, Hagi, Cardi, TinyGo (baby clothing) and others, all still at 0–1 ratings. The category was already crowded, and it's unclear who is copying whom. As of 11-06 I haven't seen anyone copy the "mom persona."

If it were you

The one-line takeaway: Don't build a "weather outfit app." Build "the sentence every mom in one language has said, that everyone recognizes." Anyone can copy the features; what's worth something is the line and the audience you built before launch.

Who it suits: 1–2 people, one of whom can write jokes and make short videos, ideally already with a few thousand to tens of thousands of followers on Instagram, RedNote, Douyin or TikTok; and one who can polish a small app within two weeks.

Who it doesn't suit: Anyone without content skills who plans to launch and then wait for search traffic. kuyara is the ready example: same features, 9 ratings. It also doesn't suit anyone expecting big money from it: weather apps have a low paid ceiling, and HIRKA's own revenue isn't proven yet.

How to do it:

• Pick a "parent-voice nags you about what to wear" joke that's already deeply rooted. Chinese already has one: "There's a cold that exists only because your mom thinks you're cold," plus the long johns. Japanese, Korean, Polish and Arabic probably have equivalents (inferred, not checked one by one). One persona per language, not a translation.
• Follow its sequence: first post a concept video, "imagine an app like this," stating "not real yet," and treat the comments as the waitlist; if people respond, spend two weeks building it and announce launch under the same video. If the reaction is weak, try a different line; the cost is one video.
• The product does one thing: one-sentence decisions, one notification a day, one widget. Shareable items (report card, outfit card) stay in the free tier, and you charge for personalization, like the wardrobe, what the kids wear, or travel packing.

How to get users: No paid acquisition. A concept video, a launch video, and a brand account posting one city outfit card a day: those three are the whole plan. Write the store title in the words locals actually search for "what to wear today." Pick a small chart like weather, where a few dozen ratings can take the top spot; once you're there, the store brings in traffic for you.

When to do it: The hook has to land while the local seasons are actually changing. The northern hemisphere's autumn-winter transition is already past halfway; the next window is the spring transition from 2 to April (the "don't shed layers too early" saying fits perfectly). The southern hemisphere is entering its transition now.

Signs you've misread it: ① After December, HIRKA drops out of Turkey's weather top 10, and ratings rise by only single digits a day. That means it relied on the season plus a one-off joke, didn't hold users, and followers only eat one season. ② You post the concept video and no one asks where to download. Then the line isn't universal enough: change it, don't force it. ③ The reverse: HIRKA reaches the Turkey weather grossing chart. That means these users will pay for "mom picks your clothes," the approach doesn't just grow users, it makes money, and you should move fast.

Data and sources

• App Store charts, rating counts and reviews by store: 10-28 to 11-06; Google Play installs and charts: 11-06.
• Puoi Studio case study puoistudio.nl/projects/hirka, the official site hirka.app (pricing, cutoffs, notification copy), 11-06.
• Instagram: Selinay İblikci's Reels (10-13, 11-02), @hirka.app posts (10-30, 11-03 to 11-05); posting dates inferred from post IDs.
• Searched "hirka app" on TikTok and X: 11-06, no relevant content found.
• No public revenue figure. "About $9 / month" is estimated at the exchange rate.