Comparison

TheStack Baseball vs CSP Amplify

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

Head to head
About

TheStack Baseball

Enhance your baseball performance by increasing bat speed through dynamic, personalized training programs. Track your progress, connect with other players and coaches, and optimize your workouts for maximum gains. Requires a Stack Bat to begin.

Highlights
  • Dynamic training programs
  • Personalized speed trainer
  • Track speed and metrics
  • Connect with other players
  • Team monitoring for coaches
  • Variable inertia speed training
Features
Read full description

Biohack your Bat Speed so that you can swing faster & play better. From the team that brought you the Award-Winning Stack System loved by over 45,000 golfers, Dr. Sasho MacKenzie has now applied his years of speed research to create the most effective way to increase your bat speed. Players, Coaches, and Organizations across all levels of baseball can now systematically gain bat speed to hit the ball harder, farther, and have more success at the plate. What’s Inside TheStack Baseball App: * Dynamic Training Programs Customized variable inertia speed training (precision overload and overspeed) - the most efficient way to increase your bat speed. The App responds to your progress and continuously optimizes your training. The algorithms that power dynamic programming come from years of research by leading sports scientist, Dr. Sasho MacKenzie and insights from over 25 million swings from The Stack System golf’s solution. * Your Own Personal Speed Trainer Be guided through scheduled workouts while tracking Stack weight, rest, recovery, and performance gains. This information allows future workouts to be adjusted behind the scenes, so your training is optimized to maximize bat speed gains. * Track Speed, Share Metrics Seamless connection to the Stack Sensor, which is integrated into the TheStack Bat. Train anywhere, anytime. Track key performance metrics such as Stack Speed, Distance Potential, Bat Speed and Grit Score. Easily share your progress and gains. * Connect to Others Easily connect and follow other Stackers' progress and keep each other on track with your training. If you’re a Coach, add your whole team and monitor progress. *** To start speed training, you will need a Stack Bat. Terms of Use: http://www.apple.com/legal/itunes/appstore/dev/stdeula

About

CSP Amplify

Access expert-designed exercises and personalized training programs trusted by professional athletes. Features hundreds of professionally filmed demonstrations, clear technique instructions, and progress tracking to help you maximize your performance. Optimized for serious athletes and fitness enthusiasts.

Highlights
  • Expert exercise library with hundreds of demonstrations
  • Personalized training recommendations
  • Progress tracking and workout history
  • Curated workout programs
  • Offline video playback
  • Dark mode support
Features
Read full description

CRESSEY SPORTS PERFORMANCE - ELITE TRAINING, ANYWHERE Transform your training with the official Cressey Sports Performance mobile app. Get instant access to the same expert-designed exercises and programs trusted by professional athletes, collegiate teams, and serious fitness enthusiasts worldwide. WHAT YOU'LL GET EXPERT EXERCISE LIBRARY Hundreds of professionally filmed exercise demonstrations Clear technique instructions and coaching cues Categorized by movement patterns, equipment, and training goals High-quality video playback with detailed form breakdowns PERSONALIZED TRAINING Smart exercise recommendations based on your experience level Customized workout collections for your specific goals Progress tracking to monitor your training journey Favorite and bookmark exercises for quick access ORGANIZED COLLECTIONS Curated workout programs for different training phases Exercise progressions and regressions Sport-specific training protocols Injury prevention and corrective exercise sequences TRAINING NOTES & HISTORY Add personal notes to any exercise Track your exercise history and frequency Review past workouts and training sessions Build your personalized exercise database WORLD-CLASS EXPERTISE Access proven training methods from Eric Cressey and the CSP coaching team — the same professionals who have worked with: MLB All-Stars and World Series Champions NFL Pro Bowlers and Super Bowl Champions Olympic athletes and elite performers Thousands of dedicated athletes at all levels SEAMLESS EXPERIENCE Smooth, intuitive interface designed for athletes Offline-capable video playback Background audio support for music while training Full-screen video mode for detailed viewing Dark mode optimized for gym environments POWERFUL FEATURES Advanced filtering and search capabilities Multiple category organization Equipment-based exercise sorting Regular content updates with new exercises Cloud sync across all your devices WHO IT'S FOR Serious athletes looking to maximize performance Strength and conditioning professionals Personal trainers seeking expert exercise demonstrations Fitness enthusiasts committed to proper technique Anyone wanting access to world-class training methods ABOUT CRESSEY SPORTS PERFORMANCE CSP has been at the forefront of sports performance training for over two decades. Our evidence-based approach combines cutting-edge research with real-world application, helping thousands of athletes achieve their goals safely and effectively. Founded by renowned performance coach Eric Cressey, CSP has become the go-to resource for athletes who refuse to settle for average. Our training methods are backed by science, proven by results, and now available in the palm of your hand. SUBSCRIPTION REQUIRED This app requires an active CSP subscription to access content. Visit ericcressey.com to learn more about membership options and start your journey to peak performance. SUPPORT Questions or feedback? Our team is here to help: Email: support@ericcressey.com Website: www.ericcressey.com Train smarter. Perform better. Download the CSP app today.

Screenshots

TheStack Baseball4 screens
CSP Amplify4 screens

Verdict

The call

TheStack Baseball and CSP Amplify both sit at 4.9 stars, but that hides the real split: 100% of CSP Amplify's written reviews are positive against 0% of TheStack Baseball's. CSP Amplify also leads on ads (none vs shown) and iOS requirement (13.0 vs 15.0). TheStack Baseball's advantage is monetization model (ad-supported vs subscription) and ratings volume (87 vs 14). On price, rating, update cadence and in-app purchases 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. Neither carries in-app purchases, so what you see is what you pay.

ReceptionRating · Positive reviews · Number of ratings

On the App Store both sit at effectively the same score — 4.9 for TheStack Baseball against 5.0 for CSP Amplify. That said, the two scores are not equally well evidenced: TheStack Baseball has 87 ratings behind it against 14, so its average is the more settled of the two. Written reviews are what separate them: 0% of TheStack Baseball's written reviews are positive against 100% of CSP Amplify's.

UpkeepUpdate frequency

TheStack Baseball ships an update every 2 months, CSP Amplify monthly. The most recent releases landed on October 20, 2026 and October 2, 2026 respectively.

Scorecard5 real differences · 5 level
TheStack Baseball versus CSP Amplify: the parameters behind the verdict, then further details
ParameterTheStack BaseballCSP Amplify
PriceFreeFree
Rating4.9 (87 ratings)5.0 (14 ratings) — better
Positive reviews0.0% of reviews100.0% of reviews — better
Number of ratings87 — better14
Update frequencyEvery 2 monthsMonthly — better
AdsYesNo — better
In-app purchasesNoNo
MonetizationAd-supported — betterSubscription
DevicesiPhone, iPodiPhone, iPod
Requires iOS15.013.0 — better
Further details — not scored
Size121 MB62 MB
Age rating4+4+
DeveloperThe Stack System Baseball GP, Inc.Cressey Training Systems, LLC

Customer experience

TheStack Baseball

All ratings53 ratings
Positive98.1%
Neutral1.9%
Negative0.0%
Written reviews1 reviews
Positive0.0%
Neutral0.0%
Negative100.0%

CSP Amplify

Written reviews10 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

In-app purchases

None

TheStack Baseball

No in-app purchases

None

CSP Amplify

No in-app purchases

Questions

Is TheStack Baseball free?
TheStack Baseball is free to download, with no in-app purchases.
Is CSP Amplify free?
CSP Amplify is free to download, with no in-app purchases.
Which has better reviews, TheStack Baseball or CSP Amplify?
CSP Amplify is rated higher. TheStack Baseball averages 4.9 out of 5 from 87 ratings, while CSP Amplify averages 5.0 from 14 ratings.
Do TheStack Baseball or CSP Amplify have ads?
TheStack Baseball shows ads; CSP Amplify does not.
Which is updated more often, TheStack Baseball or CSP Amplify?
TheStack Baseball ships an update every 2 months, and CSP Amplify monthly. Most recently, TheStack Baseball was updated on October 20, 2026 and CSP Amplify on October 2, 2026.

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