Doomsday Trainer

Name: Doomsday Trainer
Author: Sum And Product

By: Sum And Product App

An app to help training John Conway's Doomsday Algorithm

This app was removed from Google Play Store on 2026-06-08

Overview

Removed

Downloads

660

Data as of 2026-06-08

Version:

3.0.2

Last updated: 2025-09-11

Features & Capabilities

This app helps you train the Doomsday Algorithm which allows you to quickly deduce the day of the week to any given date within seconds.

It was invented by John Conway in 1973. Here, a variant is used which was found by Fong and Walters in 2010.

For more information and an in-depth explanation of the algorithm please see the Wikipedia article. But the app contains a condensed explanation and also detailed practice modes for the three major steps in the algorithm.

User Growth & Download Statistics

App

By:

Sum And Product

Downloads:

660

Version:

3.0.2 Last updated: 2025-09-11

Version code:

Creation date:

2020-09-09

Publisher country:

Size:

39.85MB

Email:

su*****@gmail.com

URLs:

Full description:

Source:

Google Play Store

Data ingested on:

2026-06-08

Compare stats and ranking:

Contact the developer

Chrome-Stats does not own this Android app. Please use these information below to contact the Android app developer.

Developed by:

Sum And Product

Google Play Store

https://play.google.com/store/apps/details?id=org.godotengine.doomsday

Email:

su*****@gmail.com

User Reviews

Great training tool - exactly what you need to improve your times for Doomsday date calculation. Love the stats tracking. The explanations are quite algorithmic / code-y, which won't suit everyone. I had not used the "odd+11" method before & learned it through this app, but my advice is don't ditch this app just if it's not the easiest way to learn the method for a beginner. Learn whatever method you like from wherever you like, then use this app for speed training! Thanks for this app!

Da*****, 2023-07-15

Excellent Doomsday Trainer, could use a little more customization. I wish you could select individual centuries to train, it'd be nice to exclude the 1800s and just practice birthdays you're likely to encounter.