Comparison

ESP Trainer vs Blackjack 21

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

Head to head
About

ESP Trainer

Enhance your psychic abilities with this ESP trainer. Developed under a NASA program, it helps you improve clairvoyant skills through interactive color-square guessing games. Experience multi-sensory feedback and learn to recognize intuitive impressions.

Highlights
  • Color-square guessing game
  • Multi-sensory feedback (chime, vibration, visual)
  • Score tracking and encouragement
  • Optional 'Pass' button for non-forced choices
  • Reinforcement for skill learning
  • Develop intuitive awareness
Features
Currently charting
Read full description

The ESP trainer was developed under a NASA program by Russell Targ at Stanford Research Institute. We have found that people are able to improve their ESP scores by using a machine just like this and get in touch with the part of themselves that is psychic. This is often called a clairvoyant ability, and can enhance your life in many surprising ways. The player is presented with four colored squares. For each trial, one has been selected at random by the ESP Trainer. Your task is to choose the correct square. If you succeed, you will hear a chime, feel a vibration, and see a large color picture. Otherwise, the system lights up the correct square, and you proceed with the next trial. The score indicator at the top counts the number of correct choices. Words of encouragement appear as you achieve the scoring levels of 6, 8. 10, 12 or 14 hits. After 24 trials you may begin a new game. The game offers multi-sensory feedback, reinforcement, and an opportunity to Pass, meeting all the requirements needed for learning this skill. ESP Trainer improves your ability to recognize your intuitive impressions, and it can bring you to a level of intuitive awareness beyond anything you've experienced before. The purpose of the trainer is to allow you to become aware of what it feels like when you psychically choose the correct square. When you don't have that special feeling, we encourage you to press the Pass button. (So this is not a "forced choice" test.) In a year long NASA program with 145 subjects (under Contract 953653 NAS7-100) many were able to significantly improve their scores. Four of the subjects improved their scores at the hundred-to-one level or better. This approach has been used with surprising success on Wall Street. But of course, past results are no guarantee of future performance. Because you are learning a new skill, slower is better than faster. If you find yourself frequently scoring 12 or more, write to the developer at his web site www.espresearch.com. This game can provide the first steps toward experiencing and developing the psychic abilities hidden within us all. software by Levity Novelty LLC

About

Blackjack 21

Master blackjack with this strategy trainer. Learn optimal decisions for hitting, standing, splitting, doubling, and surrendering through realistic hands and instant feedback. Improve your confidence and decision-making at the table without any real money or distractions.

Highlights
  • Practice real blackjack decisions
  • Get instant feedback on moves
  • View adaptive basic strategy table
  • Learn professional playing techniques
  • No money or card counting involved
Features
Read full description

Make Better Decisions at the Blackjack Table Learn exactly when to Hit, Stand, Split, Double or Surrender - and why. Blackjack 21: Strategy Trainer is your personal guide to basic strategy. It teaches you the fundamentals through real hands and instant feedback ⋄ Practice Real Blackjack Decisions Hit, Stand, Split, Double or Surrender — train your choices on realistic hands. ⋄ Get Instant Feedback See if your move matches basic strategy, and understand why it was right or wrong. ⋄ View the Basic Strategy Table Access a full strategy chart that adapts to your selected house rules. ⋄ Learn to Play Like a Professional Build confidence and make better decisions through structured practice. ⋄ No Money, No Counting, No Distractions This is a Blackjack training app, not a game. There’s no simulated or real money, and no card counting involved. ___________________________ What Users Say ⋆⋆⋆⋆⋆ "I finally know when to double or surrender. Love having the strategy table in my pocket." ⋆⋆⋆⋆⋆ "This really helped me understand the game and make better decisions." ⋆⋆⋆⋆⋆ "I use it before every casino trip – best blackjack training app out there!" ___________________________ Terms: www.bjt.app/terms-of-use Privacy: www.bjt.app/privacy-policy

Screenshots

ESP Trainer4 screens
Blackjack 214 screens

Verdict

The call

The clearest difference is price: Blackjack 21 at Free against ESP Trainer's $0.99. Blackjack 21 also leads on update cadence (fortnightly vs every 14 months) and ratings volume (5.7K vs 293). ESP Trainer's advantage is in-app purchases (none vs 13) and review sentiment (75% vs 55%). On ads 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

Blackjack 21 is free to download; ESP Trainer costs $0.99 up front. Blackjack 21 sells 12 in-app purchases, starting at $4.99 per month. ESP Trainer asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

Blackjack 21 holds the better App Store score, 4.7 against 4.5. That said, the two scores are not equally well evidenced: Blackjack 21 has 5.7K ratings behind it against 293, so its average is the more settled of the two. Written reviews complicate that: 75% of ESP Trainer's written reviews are positive against 55% of Blackjack 21's, so the app with the better star average is not the one people write more warmly about.

UpkeepUpdate frequency

ESP Trainer ships an update every 14 months, Blackjack 21 fortnightly. Both last shipped on November 1, 2026.

Scorecard9 real differences · 2 level
ESP Trainer versus Blackjack 21: the parameters behind the verdict, then further details
ParameterESP TrainerBlackjack 21
Price$0.99Free — better
Rating4.5 (293 ratings)4.7 (5.7K ratings) — better
Positive reviews75.2% of reviews — better54.9% of reviews
Number of ratings2935.7K — better
Update frequencyEvery 14 monthsFortnightly — better
AdsNoNo
In-app purchasesNo — betterYes
MonetizationFree — betterFree with in-app purchases
Best chart rank#5 — better#162
DevicesiPhone, iPodiPhone, iPad
Requires iOS7.0 — better16.0
Further details — not scored
Size16 MB69 MB
Age rating4+12+
DeveloperRussell TargBlackJack Trainer 21 Training AG

Customer experience

ESP Trainer

All ratings293 ratings
Positive84.6%
Neutral6.5%
Negative8.9%
Written reviews113 reviews
Positive75.2%
Neutral13.3%
Negative11.5%

Blackjack 21

All ratings5,661 ratings
Positive92.7%
Neutral3.5%
Negative3.8%
Written reviews224 reviews
Positive54.9%
Neutral11.6%
Negative33.5%

User reviews

ESP Trainer

From 293 App Store ratings

What we love

  • 👍 Simple and effective
  • 🤩 Helps develop intuition
  • 🧠 Trains psychic abilities
  • 🎯 Accurate feedback on performance
  • 🌟 Impressive high scores possible

Room to improve

  • 🔇 Loud, annoying sound effects
  • 🔍 Lack of performance tracking/history
  • 🐛 Occasional bugs and glitches
  • 🤔 Questionable scientific validity

Blackjack 21

From 5.7K App Store ratings

What we love

  • 🚀 Great training
  • 👍 Helpful for practicing basic strategy
  • 👍 Solid interface
  • 👍 Detailed feedback
  • 👍 Easy to use UI

Room to improve

  • 🐛 Buggy with pop-ups and crashes
  • 🔒 Subscription model for full functionality
  • 🔒 Paywall for advanced features
  • 👎 Lacks explanation for correct/incorrect moves
  • 👎 Inaccurate basic strategy recommendations

Bugs and requests

ESP Trainer

Reported bugs

3 issues
  • Freezing or crashing on some devices
  • Inconsistent responsiveness of color squares
  • Inability to disable sound effects

Requested features

4 requests
  • Volume/sound control options
  • Performance tracking and statistics
  • More difficulty levels or game modes
  • Integration with other mindfulness apps

Blackjack 21

Reported bugs

4 issues
  • Incorrect basic strategy recommendations
  • Freezing and crashing issues
  • Incompatibility with certain devices
  • Subscription issues and unexpected charges

Requested features

6 requests
  • Allow continuing hands beyond initial deal
  • Provide explanations for correct/incorrect moves
  • Incorporate card counting and strategy deviations
  • Customize settings to match casino rules
  • Reset weakest hands chart
Show 1 more
  • Add betting options and player profiles

In-app purchases

None

ESP Trainer

No in-app purchases

12 purchases

Blackjack 21

Subscriptions8
  • All PRO features - monthly$4.991 Month
  • Flash Sale! PRO - monthly1 Month trial$7.991 Month
  • All PRO features - monthly$7.991 Month
Show 5 more
  • All PRO features - monthly$8.991 Month
  • All PRO features - yearly7 Days trial$23.901 Year
  • All PRO features - yearly3 Days trial2 variants$23.991 Year
  • All PRO features - annually3 Days trial$23.991 Year
  • Flash Sale! PRO - yearly1 Year trial$24.991 Year
One-time4
  • Pair Practice Mode$1.99
  • Soft Hand Training Mode$1.99
  • Custom Table Settings$1.99
Show 1 more
  • All PRO features - lifetime$49.99

Questions

Is ESP Trainer free?
ESP Trainer costs $0.99, with no in-app purchases.
Is Blackjack 21 free?
Blackjack 21 is free to download, with in-app purchases available.
Which has better reviews, ESP Trainer or Blackjack 21?
Blackjack 21 is rated higher. ESP Trainer averages 4.5 out of 5 from 293 ratings, while Blackjack 21 averages 4.7 from 5.7K ratings.
Do ESP Trainer or Blackjack 21 have ads?
Neither ESP Trainer nor Blackjack 21 shows ads.
Which is updated more often, ESP Trainer or Blackjack 21?
ESP Trainer ships an update every 14 months, and Blackjack 21 fortnightly. Most recently, ESP Trainer was updated on November 1, 2026 and Blackjack 21 on November 1, 2026.
Which is more popular, ESP Trainer or Blackjack 21?
ESP Trainer currently peaks at #5 in the App Store charts, and Blackjack 21 at #162. Chart position reflects recent download velocity rather than total install base.

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