FlipTheCoin.app — PWA, Browser Extension, and Blog

Created:2025
Website:https://flipthecoin.app/
Repository:https://github.com/paulmelero/flipthecoin.app/

FlipTheCoin.app is a web app and browser extension to simulate coin flips with a physics engine in the browser.

It is a simple PWA (Progressive Web App) and browser extension that allows you to simulate coin flips with a physics engine in the browser.

You can find the code on .

Coin simulation

The is powered by a physics engine that simulates the coin flip. I explained how it works in this article: and you can find the code on .

Browser extension

The is a simple extension that allows you to simulate coin flips with a physics engine in the browser.

You can find the code on .

What is interesting about the browser extension is I reuse the same physics engine code from the web app to simulate the coin flip in the browser extension. I share the code between the 2 "apps" thanks to the pnpm monorepo setup I configured and thanks to having a shared packages folder.

Blog

For now, the web is really dummy so, at least, I wanted to write some blog posts about some interesting things I learned while building it and some cool physics and probability concepts I discovered.

For me it's a way to learn more about Maths and enjoy something I am passionate about, while sharing it with others.

Why I built it

Aside from what I just mentioned, I also wanted to build a more complex game involving coin flips. At the same time, I have mixed feelings about games that could become too addictive. And this one, being about a coin..., I just despise everything related to gambling and casinos. So, I don't want to build anything that could trigger anxiety or addiction issues. I am being cautious not to use the same imagery as traditional games that are strongly related to "coin games". For now, the plans to build a more complex game are on hold, but I might come back to it later.

This is another reason why I started the blog with knowledge-sharing posts. I want the site to be useful for others. Something math enthusiast or students can find funny and instructive.