# Doomsday Method | Mental Game vs Day Genius

The clearest difference is in-app purchases: Doomsday Method | Mental Game at none against Day Genius's 1. Doomsday Method | Mental Game also leads on ratings volume (3 vs 1) and iOS requirement (17.0 vs 26.0). Day Genius's advantage is rating (5.0 vs 4.7) and update cadence (every 2 weeks vs monthly). On price, review sentiment, ads and device support there is nothing between them.

Both are free to download. Day Genius sells 1 one-off in-app purchase. Doomsday Method | Mental Game asks for nothing beyond the download.

Day Genius holds the better App Store score, 5.0 against 4.7. Both are backed by a comparable volume of ratings — 3 and 1 respectively. Written reviews split almost evenly too, at 100% and 100% positive.

Doomsday Method | Mental Game ships an update monthly, Day Genius every 2 weeks. Both last shipped on October 14, 2026.

## The numbers

| Metric | Doomsday Method | Mental Game | Day Genius |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [4.7 (3 ratings)](https://appshunter.io/ios/app/doomsday-method-mental-game/id6447447000/reviews) | **[5.0 (1 ratings)](https://appshunter.io/ios/app/day-genius/id6801888644/reviews)** |
| Number of ratings | **3** | 1 |
| Positive reviews | 100.0% of reviews | 100.0% of reviews |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Monthly | **Every 2 weeks** |
| Monetization | **Free** | Free with in-app purchases |
| Size | 10 MB | 6 MB |
| Requires iOS | **17.0** | 26.0 |
| Devices | iPhone | **iPhone, iPad** |
| Age rating | 4+ | 4+ |
| Developer | [Leon Grimmeisen](https://appshunter.io/developer/1654025400) | [Craig Ricks](https://appshunter.io/developer/6801888646) |

## What reviewers say

### Doomsday Method | Mental Game

[App page](https://appshunter.io/ios/app/doomsday-method-mental-game/id6447447000)

Master the art of calculating weekdays for any date with this comprehensive educational app. Learn a proven technique, practice with interactive exercises, and track your progress to sharpen your mental arithmetic skills.

**Highlights:** Learn Doomsday Method principles, Interactive examples and tips, Dedicated training mode, Progress tracking and statistics, User-friendly interface

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases:** none


### Day Genius

[App page](https://appshunter.io/ios/app/day-genius/id6801888644)

Learn to calculate the weekday for any date without a calendar or phone. This app teaches a step-by-step method with interactive drills and games to master the skill. Unlock advanced features with a one-time purchase.

**Highlights:** Step-by-step weekday calculation method, Interactive drills and flashcards, Two engaging practice games, Progress tracking and weak-spot identification, Reference tables for calculations, Support for historical calendar rules

**Features:** macOS Compatibility, Family Sharing

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Full Method | $3.99 | one-time |


## Frequently asked questions

### Is Doomsday Method | Mental Game free?

Doomsday Method | Mental Game is free to download, with no in-app purchases.

### Is Day Genius free?

Day Genius is free to download, with in-app purchases available.

### Which has better reviews, Doomsday Method | Mental Game or Day Genius?

Day Genius is rated higher. Doomsday Method | Mental Game averages 4.7 out of 5 from 3 ratings, while Day Genius averages 5.0 from 1 ratings.

### Do Doomsday Method | Mental Game or Day Genius have ads?

Neither Doomsday Method | Mental Game nor Day Genius shows ads.

### Which is updated more often, Doomsday Method | Mental Game or Day Genius?

Doomsday Method | Mental Game ships an update monthly, and Day Genius every 2 weeks. Most recently, Doomsday Method | Mental Game was updated on October 14, 2026 and Day Genius on October 14, 2026.

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*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*