A teacher selling 5,000-lira study books turned his question bank into "Who Wants to Be a Millionaire": the Turkish occupational safety exam app İSG T Sınav

İSG T Sınav is a study app for Turkey's occupational safety specialist and workplace physician certification exams. It launched only at the end of July, and combined across both platforms it has only a few thousand users. It's worth a look not because the product is new, but because it shows something: in small-language licensing exams, what's valuable is a teacher who already has students. The app is just the container that moves those students in and charges them by exam date.

Nov 4, the reviews were full of "hello teacher"

On Nov 2026 4, İSG T Sınav's reviews on the Turkish App Store suddenly grew by a dozen or so, and the next day another dozen. They read less like ordinary user reviews and more like a class leaving messages for its teacher:

• "Greetings to Hakan teacher and Nurullah teacher, thank you for your hard work. We hope to get good results under your guidance. Our İSG TÜRKİYE family, one question at a time, wishing everyone success 😊✅🙏" (5 stars, 11-04)
• "Nurullah teacher made a great app. Even if I spend just 15 minutes a day, I can easily finish that day's lesson." (5 stars, 11-04)
• "His book has printing errors, but the app is quite good. Still, not having a monthly plan is really bad." (5 stars, 11-04)

The developer account is registered to Muhammed Nurullah Acar personally, and the store page links to isgturkiyesinav.com, a company that runs İSG training courses in Ankara and Istanbul and publishes its own study books. The website sells the "Derece Seti" (sprint book set) for 10 books per set, priced at 5,000 lira (original price 8,000, website, 11-06). The company's main Instagram account @isg_turkiye_sinav claims 90k followers on its website.

Those two days fell right in the exam registration window: the second 2026 İSG exam session was held on Dec 13, organized by Gazi University. Candidates had to register on Gazi's system between Nov 2 and 16 and pay a 2,200-lira exam fee (Ministry of Labour and Social Security ÇSGB announcement, Bulut Akademi exam guide).

What it is

• Question bank plus games: the core is a "Kim Milyoner" (Who Wants to Be a Millionaire)-style level format with 15 levels, 4 lifeline cards and a leaderboard. Other modes include word search, word guessing and a daily word, for memorizing İSG terminology. There's also a pre-exam cram sheet, "Hap Bilgiler", and mock exams in the real exam format.
• Covers A, B and C class occupational safety specialists, plus workplace physicians and other health staff (İH/DSP). Most competing apps only cover the safety specialist track.
• The questions are written by the institution itself. One user 10-23 wrote: "The question bank gets updated almost every week… The mock exam difficulty woke me up. It's not those soft questions that make you feel good about yourself, it's the real Gazi exam vibe."
• You can work through plenty of questions for free. Paid is a single tier: 6 months for ₺499,99 (in-app purchase on the Turkish App Store; Google Play lists one item at $9.99).

Scale

Very small, but it really does climb before the exam:

It only has ranks in Turkey. The bar for charting in Turkey's Education Top Grossing is low; placing 60–70 likely means only a few purchases a day (inferred). Revenue isn't public.

Where users come from: the company's own accounts, plus its own students

No flashy growth tactics. Nearly every source is visible:

• The company's own social accounts. @isg_turkiye_uzman 10-13 and @isg_turkiye_sinav 10-28 posted the same message: "Download and use the app through the link I posted 📍", followed by Android and App Store links. There are also Reels and Facebook group videos saying "İSG T Sınav is now available on Android and the App Store." The company also has a YouTube channel, and each book on its website comes with a "how to study" lecture video.
• Students and book buyers. The reviews cluster on two days: the launch day 7-31 and November 4–5. The content is mostly thanks to teachers and mentions of their books. The teacher most likely rallied them in group chats (inferred; no screenshot of the call-out seen). One August review says the user "found it through İSG expert Seda," so a small influencer is also passing it along.
• Exam dates. Ratings added 11-03 new reviews on 10, and 11-06 added 23 reviews, all falling inside the registration window.

Searching "isg t sınav" on TikTok returns nothing, and no one is talking about it on X or in the media. No ad campaigns showed up in the ad libraries, but not finding one doesn't mean none ran.

Where the money comes from, and where it leaks

The payment logic is simple: candidates are more willing to pay the closer they are to the exam. The leak is also clear. It sells only a 6-month tier, while most people arrive more than a month before the exam:

• "The exam is only a month and a half away, and I just wanted to buy it to run mock exams. But it only offers a 6-month plan, which is ridiculous. I'd already have bought 1, 3 or 6-month packages. Other apps' one-month plans are around 100–150 lira." (1 stars, 10-28)
• "The questions are thoughtfully made, with just one request: don't force a 6-month subscription. The exam is only 40 days away, it should let me subscribe for 1 months." (5 stars, 10-30)
• "I still have 2 months left and want to subscribe, but there's only a 5-month option, and I don't even know whether I can cancel anytime." (4 stars, 10-13)

Reviewers keep complaining that "the questions start repeating after a while" (9-09, 11-03). That's the easiest gap for a quiz app to fill.

Who it's competing with

Search "İSG" in the Turkey App Store and you'll find a whole crowd of indie-dev study apps (App Store Turkey ratings, 11-06):

Anyone can make a question bank, and in 2026 years a dozen new ones have appeared. What sets this one apart is that the questions, the book, the course and the app all come from one teacher, so the students are already there. Reviewers praise the gamification ("never thought studying İSG could be this fun"), but that alone wouldn't have gotten it off the ground.

If it were you

One-line verdict: It took off because one teacher already had students and followers, and you don't have that. What you can copy is the model: "a teacher with students + gamified question bank + pricing tied to exam dates." Find a teacher in another minor-language licensing exam who doesn't have an app yet and partner with them. The opportunity is real, but each market is small and there are only two or three exam sittings a year.

Who it suits: Indie devs or small teams who can quickly build a question bank with a small game layer, and who are willing to split revenue with offline teachers or publishers. Also anyone who already teaches a licensing exam and has a student group.

Who it doesn't suit: Anyone counting on App Store search for cold traffic (a dozen question banks are already fighting over the single term "İSG"); anyone aiming to go global with one product; anyone who can't handle revenue spiking and crashing twice a year with the exam calendar.

How to do it:

• Find exams: Look for licensing exams with a national standardized test, tens of thousands of candidates a year, and strong local content. Examples in Turkey are KPSS, the private security ÖGG and the accountant SMMM, or similar exams in other countries.
• Find teachers: Start with teachers who already teach the exam on Instagram or YouTube and sell books or courses. Build an app under their name, with the questions written by them and revenue split. They need someone to keep the bank updated and fight piracy. You get their student base.
• Fix what it gets wrong: sell access in three tiers based on how far away the exam is (1 months, 3 months, until exam day). Make the bank big enough that questions don't repeat, let users redo wrong answers, and offer a final-two-weeks crash pack.

How to get users: Not paid acquisition, but the teacher's accounts and student group. Post a link on launch day and again when registration opens, ask students in the group to rate the app, and put a download link under every video lesson. Only later think about spending a bit on Instagram ads ahead of exam dates, targeting people who follow these teachers.

When to start: Work backwards from the exam date. A sitting's peak runs from registration opening to the exam, about a month and a half, so the app should be live at least a month before registration opens, giving the teacher's posts something to point to. This İSG sitting (12-13) is already too late; the next one is spring 2027, and other exams each have their own dates.

What would mean you got it wrong: If after the Dec 13 exam its ratings and installs fall back to zero, and the spring 2027 sitting doesn't bring it back to November's levels, then this kind of app is just a bonus given away by a training institute to sell books and courses, and it can't support a business on its own. If it grows next round, or other İSG institutes start building their own apps, then the "teacher + app" model works for this kind of exam and is worth copying to other exams.