Comparison

QuantQwik vs 66 Days

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

QuantQwik

This app offers cognitive training and mental math drills specifically designed for quantitative finance candidates. It simulates the pressure and structure of real interview assessments, focusing on speed, precision, and decision-making skills.

Highlights
  • Cognitive, mental math, and problem-solving assessments
  • Simulates interview timing and pressure
  • Fast arithmetic drills
  • Attention and cognitive control tasks
  • Memory and spatial reasoning challenges
  • Risk-assessment mini games
Features
Read full description

QuantQwik is the first iOS app built specifically for quantitative candidates, offering a complete set of cognitive, mental math, and problem-solving assessments inspired by the types of tests used in modern quantitative finance interviews. Candidates preparing for roles at firms like Jane Street, Optiver, IMC Trading, SIG, HRT, Citadel, and Two Sigma will find training that resembles the timing, pressure, and structure of real industry screens. QuantQwik brings together fast arithmetic drills, attention-control tasks, spatial reasoning challenges, memory tests, and risk-assessment mini games into one clean and polished platform. Unlike typical brain training apps, QuantQwik focuses on the exact cognitive skills that matter in quant interviews: speed, precision, numerical intuition, focus, working memory, and decision-making under uncertainty. Inside the app, users can practice a wide range of assessments. Mental math and numerical speed are trained through Quick Calc, 80 in 8, Percent Pro, Fraction Duel, and Number Sense. Attention and cognitive control are developed through Arrow Storm, Lightning Tap, and Spot the Switch. Memory and spatial reasoning are strengthened through Memory Matrix, 3D Mental Rotation, and Tower of Hanoi. Decision-making and risk evaluation are trained through Balloon Risk, which is inspired by behavioral assessment tools used in trading evaluations. The experience is designed to feel premium and focused. The interface uses smooth animations, refined typography, no ads, and intuitive visuals. All data is synced through iCloud, and the app is optimized for both iPhone and iPad. Performance metrics update as you train, showing accuracy, speed, streaks, reaction times, and personal bests for every assessment. Whether you are practicing for mental-math rounds, cognitive screens, or fast-paced numerical tasks, QuantQwik gives you structured preparation built around quant expectations. Free users have access to the essential assessments. A premium subscription unlocks all twelve assessments, the full statistics dashboard, custom practice reminders, and future premium features. QuantQwik is ideal for quant trading and research candidates, STEM students, competitive exam takers, and anyone who wants to improve cognitive performance in a measurable way. --- SUBSCRIPTION INFORMATION QuantQwik Premium offers two auto-renewing subscription options: • Monthly Subscription: Billed monthly, cancel anytime • Yearly Subscription: Billed annually, cancel anytime Subscription benefits include: • Access to all 12 premium assessments • Advanced performance analytics • Practice reminders and notifications • Full iCloud sync across devices Payment will be charged to your iTunes Account at confirmation of purchase. Subscription automatically renews unless auto-renew is turned off at least 24 hours before the end of the current period. Your account will be charged for renewal within 24 hours prior to the end of the current period. You can manage and cancel your subscriptions by going to your account settings on the App Store after purchase. Terms of Use: https://quantqwik.com/terms Privacy Policy: https://quantqwik.com/privacy

About

66 Days

Master banking and consulting interviews with daily AI-powered practice. Track your progress on a 66-day journey with personalized feedback on technical, behavioral, and case questions. Improve your resume and gain confidence for top firms.

Highlights
  • AI interview coach with personalized feedback
  • Daily drills for behavioral, technical, and case questions
  • 66-day progress heat map
  • Resume checker
  • Excel and valuation tools
  • Analytics dashboard
Features
Read full description

66 Days Prep is an AI-powered career preparation platform designed to help candidates master interviews for banking and consulting roles through structured, daily progress. The app combines personalized coaching, habit tracking, and analytics to transform your preparation into a consistent 66-day journey. Each day you’ll train across behavioral, technical, cases or market-based questions while receiving instant feedback from an AI coach. The goal is simple — make interview mastery a daily habit. Your progress is visualized through a 66-day heat map that tracks consistency, focus, and improvement. Every session compounds your learning so that when interview season arrives, you’re confident, sharp, and ready to perform. Key features: • AI interview coach for personalized feedback on real questions • Daily drills in behavioral, technical, cases, and market news • 66-day heat map that tracks performance and consistency • Resume checker to strengthen clarity and impact • Excel and valuation tools for technical accuracy • Productivity features including timers and streak reminders • Analytics dashboard that highlights your growth over time Built by former bankers and consultants, 66 Days Prep mirrors real recruiting standards at leading firms such as Goldman Sachs, Morgan Stanley, McKinsey, and Bain. The app ensures that every minute spent practicing is focused on what matters most — structured thinking, confident delivery, and business intuition. Whether you are recruiting for your first internship, preparing for post-graduate consulting interviews, or advancing your career in finance, 66 Days Prep provides a disciplined path to daily improvement. Consistency is what separates good candidates from great ones. 66 Days Prep helps you build that consistency through smart repetition, clear feedback, and visible progress you can track. Build momentum, develop confidence, and master your interviews with 66 Days Prep — your AI career partner for banking and consulting success. Some features, including the AI interview coach, require a subscription. Please review our Privacy Policy at https://www.66daysprep.com/privacy. By using this app, you agree to the terms outlined in https://www.66daysprep.com/terms and https://www.apple.com/legal/internet-services/itunes/dev/stdeula/.

Screenshots

QuantQwik4 screens
66 Days4 screens

Verdict

The call

The clearest difference is in-app purchases: QuantQwik at none against 66 Days's 2. 66 Days's advantage is rating (4.9 vs 4.5) and ratings volume (228 vs 6). On price, ads, monetization model 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

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. 66 Days sells 2 in-app purchases, starting at $15.99 per month. QuantQwik asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

66 Days holds the better App Store score, 4.9 against 4.5. That said, the two scores are not equally well evidenced: 66 Days has 228 ratings behind it against 6, so its average is the more settled of the two. Written reviews point the same way: 33% of QuantQwik's written reviews are positive against 50% of 66 Days's.

UpkeepUpdate frequency

QuantQwik ships an update monthly, 66 Days every 10 days. The most recent releases landed on October 3, 2026 and October 7, 2026 respectively.

Scorecard5 real differences · 5 level
QuantQwik versus 66 Days: the parameters behind the verdict, then further details
ParameterQuantQwik66 Days
PriceFreeFree
Rating4.5 (6 ratings)4.9 (228 ratings) — better
Positive reviews33.3% of reviews50.0% of reviews — better
Number of ratings6228 — better
Update frequencyMonthlyEvery 10 days — better
AdsNoNo
In-app purchasesNo — betterYes
MonetizationFreemiumFreemium
DevicesiPhone, iPadiPhone, iPad
Requires iOS17.617.0 — better
Further details — not scored
Size7 MB110 MB
Age rating4+4+
DeveloperShubham TiwariUru Technologies, LLC

Customer experience

QuantQwik

Written reviews3 reviews
Positive33.3%
Neutral33.3%
Negative33.3%

66 Days

All ratings228 ratings
Positive96.9%
Neutral1.3%
Negative1.8%
Written reviews6 reviews
Positive50.0%
Neutral16.7%
Negative33.3%

In-app purchases

None

QuantQwik

No in-app purchases

2 purchases

66 Days

Subscriptions2
  • 66 Days Prep Pro$15.991 Month
  • 66 Days Prep Pro$49.991 Year

Questions

Is QuantQwik free?
QuantQwik is free to download, with no in-app purchases.
Is 66 Days free?
66 Days is free to download, with in-app purchases available.
Which has better reviews, QuantQwik or 66 Days?
66 Days is rated higher. QuantQwik averages 4.5 out of 5 from 6 ratings, while 66 Days averages 4.9 from 228 ratings.
Do QuantQwik or 66 Days have ads?
Neither QuantQwik nor 66 Days shows ads.
Which is updated more often, QuantQwik or 66 Days?
QuantQwik ships an update monthly, and 66 Days every 10 days. Most recently, QuantQwik was updated on October 3, 2026 and 66 Days on October 7, 2026.

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