"Where's the train?" worth 5 taka per text: a free train tracker built in Bangladesh by a Flutter instructor

Bangladesh Railway has no official real-time location lookup. To find out where a train is, you pay about 5 taka for an SMS. An indie developer who teaches Flutter built TrainKothai, a free crowdsourced locator. It hit 170k installs in 5 months with zero ad spend. But it's only the number-two player in this niche, and the leader has more than three times its volume. Below: how it grew, who it's competing with, and how much room this playbook has left in other countries.

A LinkedIn post

In Sep 2026 15, Bangladeshi developer Abu Anwar posted a two-line update on LinkedIn: "My TrainKothai.com has 50k+ downloads in three months, and 28k+ in the last 48 days. This is the power of SEO and AEO!"

Abu Anwar isn't a transport person. He is a Google-certified Flutter Developer Expert (GDE) with a YouTube channel, The Flutter Way, that has 230k subscribers, and he mostly teaches people how to write apps. TrainKothai is his side project; the name means "where is the train" in Bengali. The Android version launched in May 21 and the iPhone version in Jul 9. In Oct 24 he spoke at DevFest in Troy, New York, on "how my side app reached 100k+ downloads in 5 months." In Nov 5, Bangladeshi outlet Deepto News covered it, by which point the figure was 170k+.

The Google Play numbers match his claims: 10-29 is 131,916 installs and 11-06 is 170,511, up over 38,595 in a week.

What it is

Open the web page or the app, enter a train number, and you see on a map where it is now, how late it is and how fast it's going. Location comes from three sources (per the about page on the official site):

• Passengers on board: someone opens "I'm on the train" in the app, and their phone GPS anonymously updates that train's position.
• Official timetable: when no one on board is sharing, it estimates a rough position from the timetable and labels it "not real-time GPS."
• Official SMS service: it also pulls the positions the railway's SMS lookup returns and shows them on the site for free.

No sign-up, fully free; the Android version makes money from ads. The web version works without installing anything, and roughly 200 trains nationwide each have their own page.

Why now: one SMS costs 5 taka

Bangladesh runs about 350 intercity trains a day, carrying tens of millions of passengers a year, and delays are the norm (Deepto News). The official location lookup is texting "TR <train number>" to 16318, at about 5 taka per text. An older app, BR Explorer, charges 10 taka for 5 queries. Nothing free, and no map.

App Store reviews put it bluntly: "Nobody ever expected the Bangladesh trains to be on time, but from now on at least we'll know when they arrive" (9-14); "Free train tracking with no service fee is new for our country" (8-29); a user who has used similar apps in India writes "I've used this kind of app in India... this one is better; it would be great if the railway itself made it" (9-15).

Timing helped too. The Android version went live a week before the late-May Eid homecoming peak. The rapid growth in 9 and October overlaps with travel seasons such as Durga Puja (inference).

Where users come from: searches like "where is XX Express now"

The founder himself credits search. The site structure shows how he did it:

• One searchable page per train. For example, someone searches Google for "where is Subarna Express now" and lands on that train's page on trainkothai.com, then gets nudged to install the app. There is also a Bengali-language site at /bn.
• Store descriptions written as Q&amp;A: "Is TrainKothai the official train tracking app?" "Is TrainKothai free?" These are written to be quoted by Google summaries and AI answers (AEO).
• Use the web first, no sign-up. Rivals require a Google login first. It doesn't.

Other channels were small: a self-promo post on Reddit r/Dhaka titled "I made an app so you can track Bangladesh trains for free," the Facebook page and groups, and a press release in Nov 4. The founder has 23.5k followers on LinkedIn, but that mostly brings in peers, not passengers. No TikTok videos about it turn up in search, and the founder says he has done "zero paid promotion."

There's also a crowdsourcing effect: the more people use it on board, the more trains can be tracked in real time, the more accurate it gets, and the more people stick around. It can track 50 trains at once during peak hours (per AppBrain summary).

It isn't the first mover.

This is the part readers are most likely to miss. For the same need, Gatishil Ventures' "BD Train Tracking" shipped earlier (already at 50k+ installs before April). It has 11-06 Play installs, 590,127 in 7 days, up 180,051, and its weekly gain is more than four times TrainKothai's.

The two are neck and neck: Gatishil launched on Nov 2 and Jagonews24 covered it, then TrainKothai put out a press release two days later, and both are pushing the same "3D map to track trains" pitch.

So the more accurate framing is: the "where is my train" category in Bangladesh is breaking out as a whole, and TrainKothai captured a share of it through search. Its execution is excellent, but the category took off because of a gap in public services and holiday travel peaks, not because of anything TrainKothai alone has.

Where the money comes from

Barely any. The Android version has ads, and revenue is not disclosed (inference: ad rates in Bangladesh are low, so 170k installs can't generate much). On iOS, one four-star review warns: "Sometimes an indecent web-series ad pops up, awkward to have in front of people, so be careful when buying ads" (10-30).

Gatishil uses a subscription at 20 BDT a month, under 0.2 US dollars. In this market, the price ceiling for "where is my train" is anchored by that 5 BDT SMS.

Also, Apple has no Bangladesh store, so the iOS version is only installed in regions with large expat populations like the UK, Gulf states, and Singapore. The US store page shows 355 ratings averaging 4.63 stars (11-06), and its best chart position was #35 in the Belize Travel Free chart. iOS numbers can't tell you how much it's used at home.

Could it work in another country?

After reading this, the natural idea is: find a country without real-time rail tracking, and copy the whole stack: crowdsourced GPS, a timetable fallback, and a page for every train. 11-06 checked the countries people most often think of:

• Pakistan: the railway itself runs Pak Rail Live real-time tracking, and older apps like Pak Railway exist;
• Sri Lanka: RDMNS.LK has been on the App Store for 2018 years and is already crowd-sourced live train status from passengers;
• Egypt: "Egypt Trains | قطارات مصر" already shows route-based live position estimates;
• Nepal: the rail network is small, and locals have already built train.chalyo;
• There are also country-by-country timetable tracking sites such as trainstracking.com and trains.fyi, which already capture English searches for "live location of trains in [country]."

In other words, Bangladesh was one of the gaps filled later, and it still attracted more than five entrants within five months. "Find the next country nobody has built for" is possible, but you'd have to check one country at a time, and what's left will most likely be small markets.

If it were you

Grade C: you can learn a clean "search cold-start" playbook, but following it is not worth it.

One-line verdict: Bangladesh already has a leader with 590k installs and a crowd of copycats; the obvious neighboring countries already have someone; and tools like this top out low, relying on ads or subscriptions of a few cents.

Who it's for: someone who already lives in a country where railway or long-distance bus tracking is missing, speaks the local language, and wants a side project that builds users and reputation. That's what Abu Anwar got: 170k users, local media coverage, and a DevFest talk, not revenue.

Who it's not for: anyone who wants to make money from it; anyone trying to break into Bangladesh now (weekly gains after third place are only a few thousand); anyone not based locally who can't earn passenger word of mouth.

How to do it: first search in the local language for "[train number] + where / live location" and see who's in the top three. If there's no solid result, then start. Copy the three-layer data sources: passenger GPS, official timetable fallback, and any official data you can plug in. Make the web version usable first, with no login required.

How to acquire users: build one page per train and per station, with titles matching the exact query users type; write store descriptions as Q&A; post a self-promotion once in local Reddit and Facebook groups; when a rival gets media coverage, publish your own press release within two days. Launch two to three weeks before a holiday rush to catch the return-home peak.

Signs I'm wrong: ① TrainKothai's weekly Google Play gains catch up with or pass Gatishil's, which would show that "free + web + SEO" beats "login + subscription + media" and is worth copying elsewhere; ② someone publicly reports ad or subscription revenue from a tool like this above a few thousand dollars a month; ③ you find a country with tens of millions of rail passengers where the top three results for "where is my train" are still empty. Then don't hesitate.