I localised my shift calendar app into 18 languages before getting 1,000 users. Here's what I learned.

Someone close to me works 2 on / 2 off and still counted days on a printed sheet stuck to the fridge. That's what started this.

The thing that bothered me: a rotating shift pattern is completely predictable. 2 on / 2 off is a formula. But every scheduling app I looked at asks you to tap in each shift by hand, month after month, for a schedule that could be generated from four pieces of information. So I built ShiftGrid — you describe the pattern once, pick a start date, and the calendar fills itself in for years ahead.

What the market actually looks like

Search "shift schedule" on Google Play and it's mostly ad-heavy apps, paywalls in front of basic features, and required accounts for data that has no reason to leave the phone. Meanwhile the users are in a basement, on a plant floor, or in a hospital corridor with no signal. So ShiftGrid is fully offline, no account, no cloud, no ads, no subscription.

The bigger realisation: almost every well-known competitor (When I Work, Sling, Shiftboard) is a team tool for managers scheduling a crew. Nobody was building the personal version — one worker, one rota, on their own phone. That gap is the whole product.

The localisation bet

Here's the part I'd push back on if someone else told me they did it: I localised into 18 languages before having a meaningful user base. Conventional advice says validate first, translate later.

My reasoning was that shift work is not a Silicon Valley problem. It's Polish factories, Czech and Slovak manufacturing, Romanian logistics, Indonesian assembly plants, Turkish healthcare. In those markets a store listing in English converts badly, and the competition in local languages is almost nonexistent. Store keywords are also the cheapest acquisition channel I have — I'm not running ads.

The non-obvious part was that translating the keywords properly matters more than translating the app. Every country has its own vocabulary for this: French workers search "3x8" and "travail posté", Poles search "nocki" and "system 4-brygadowy", Czechs and Slovaks say "turnus", Romanians search "12/24" and "24/48", Ukrainians search "2 через 2" and "доба через дві". None of that comes out of a machine translation of "rotating shift pattern". If you localise by translating your English copy, you get grammatically correct text that ranks for nothing.

Where it is now

Android only, [X] installs, no monetisation yet. Deliberately: I'd rather find out whether people keep using it than optimise revenue on a product with no retention data.

Open questions I'm still chewing on:

1. Free with no ads and no subscription is great for reviews and terrible for a business. Paid one-time unlock for advanced features, or keep it free and treat it as a portfolio piece? Nobody in this niche seems to have solved this well.

2. Localisation clearly drove installs, but I can't cleanly separate "18 languages" from "listing improved over time". If you've measured this properly per-locale, I'd like to hear how.

3. iOS next, or go deeper on Android first?

Happy to share the ASO breakdown per language if that's useful to anyone.
https://play.google.com/store/apps/details?id=com.praslin.shiftgrid