I hated apps full of ads, so I built my own. Then I added ads.

Description and use

The author built Party Picker to replace clunky web roulette games for deciding who pays for coffee. He added a controlled ad strategy, used Flutter and AI for code and translation, and released the app worldwide on Google Play and in Korea on Toss.

Problem

The author wanted a simple way to decide who pays for coffee without repeatedly searching for online roulette or ladder games and dealing with intrusive ads.

Outcome

Party Picker was released on Google Play in 177 countries and on Toss in Korea, supporting 10 languages and 20 games, with a custom ad strategy and in‑app purchase to remove ads.

Workflow

• 1. Identify need for a quick random picker for coffee payments. 2. Design 20 games (roulette, ladder, timer, reaction, word list). 3. Build the app using Flutter. 4. Add ad logic: no full‑screen ads for first 24 h, notify before ad, offer in‑app purchase to remove ads. 5. Translate UI into 10 languages using AI and custom string‑check tool. 6. Prepare privacy policy, business registration, and payment details. 7. Submit to Google Play (all countries) and Toss (Korea only). 8. Handle platform rejections (Toss subtitle, Reddit posting rules).
• 9. Iterate on design before AI code generation to improve quality.

Evidence

After releasing it, I had to think about making money. There weren't many options for a free app I was running alone. I ended up adding ads.

Source

Ads don't interrupt a game. The app lets you know when an ad is coming. There are no full‑screen ads for the first 24 hours after installation. You can also turn ads off with a one‑time purchase.

Source

I used AI for the translations and built a small tool to check for missing strings and broken placeholders.

Source

I released the app on Google Play in 177 countries and regions. I also released it on Toss, a Korean finance super app that hosts mini apps. The Toss version is only available in Korea.

Source