Ruby Compiler vs Doomsday Trainer
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
Ruby Compiler
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Ruby Compiler is an Advanced IDE enabling you to compile Ruby Programs on your Mobile Phone for Free. It comes with a code editor with in-built syntax highlighting capabilities. Ruby Compiler is - Free with no hidden charges! - Ad-Free! - Available for all platforms! Features : 1. Compile & Run - Compile & Run Ruby Programs 2. Code Editing & Syntax Highlighting - Enables you to edit code and automatically detects and highlights syntax 3. Exercise Questions - Exercise questions to help you improve your knowledge 4. Programs with Code - All the general DSA programs with code 5. Fun Facts - Some fun facts about programming and computer science This app is brought to you by the company OnePercent, based in Bangalore, India. Website: www.OnePercent.club LinkedIn: www.Linkedin.Com/Company/Onepercent-Club/
Doomsday Trainer
Master the Doomsday Algorithm to instantly calculate the day of the week for any historical date. Engage in timed challenges, compete against others, and practice various calculation methods to improve your speed and accuracy.
- Doomsday Algorithm calculation
- Timed streak challenges
- 1-on-1 live battles
- Multiple training methods
- Targeted component drills
- Step-by-step tutorial
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Master the Doomsday Algorithm — calculate the day of the week for any date in history in seconds. PLAY Build your streak and beat the clock. Every correct answer adds to your streak; one wrong answer ends it. Compete on the global leaderboard for Longest Streak and Fastest Average Speed. BATTLE Challenge a real opponent to a live 1-on-1 race. Five dates, fastest and most accurate player wins. Elo-based ranking tracks your competitive record. TRAIN Six methods to choose from: • Doomsday — the classic anchor-day approach • Odd + 11 — the Fong-Walters mental shortcut • The Wollin Shortcut — a memory-based system using vectorized doomsdays, the Square Knot Rule, and the Wollin Calamity Table (by u/Nillows) • Conway's Method — the original algorithm by John Conway • Mod 28 — reduce any year to under 28 before calculating • Custom Mode — pick your own date range, century, or decade DRILL Targeted practice for each component: months, centuries, years, mod 7 arithmetic, and the full Wollin Shortcut drill suite. TUTORIAL New to the algorithm? The built-in tutorial walks you through everything step by step.
Screenshots
Verdict
The clearest difference is update cadence: Doomsday Trainer at every 5 days against Ruby Compiler's every 2 months. Ruby Compiler's advantage is iOS requirement (12.0 vs 15.0). On price, ads, in-app purchases and device support there is nothing between them.
Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS
Both are free to download. Neither carries in-app purchases, so what you see is what you pay.
Ruby Compiler ships an update every 2 months, Doomsday Trainer every 5 days. The most recent releases landed on October 1, 2026 and September 30, 2026 respectively.
| Parameter | Ruby Compiler | Doomsday Trainer |
|---|---|---|
| Price | Free | Free |
| Rating | — | 4.0 (2 ratings) — better |
| Positive reviews | — | 0.0% of reviews |
| Number of ratings | — | 2 — better |
| Update frequency | Every 2 months | Every 5 days — better |
| Ads | No | No |
| In-app purchases | No | No |
| Monetization | — | Free |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Requires iOS | 12.0 — better | 15.0 |
| Further details — not scored | ||
| Size | 28 MB | 15 MB |
| Age rating | 4+ | 4+ |
| Developer | OnePercent | Maarten Claessen |
In-app purchases
Ruby Compiler
No in-app purchases
Doomsday Trainer
No in-app purchases
Questions
Is Ruby Compiler free?
Is Doomsday Trainer free?
Do Ruby Compiler or Doomsday Trainer have ads?
Which is updated more often, Ruby Compiler or Doomsday Trainer?
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