Every swing powered by
future-ready AI insights.

Enhance Performance Scientifically
With simply an iPhone, b4-app helps improve your athletic performance, prevent injuries, and record your progress data, allowing you to achieve optimal performance, and surpass your limits.

Access your sports data anytime anywhere
With simply your iPhone to instantly capture advanced data no matter where you are.
Developing Partner
Former MLB star,
H.C. KUO


Discover Your
Bat Contact Point
Uncover the precise moment of impact with Bat Contact Point (BCP), our advanced AI-powered visual tracking metric. BCP pinpoints the exact location and timing of bat-ball contact, transforming each swing into actionable data. The resulting insights reveal contact patterns, support mechanical adjustments, and empower players and coaches to train smarter and perform better.



Nathan, A. M. (2003). Characterizing the performance of baseball bats. American Journal of Physics, 71(2), 134–143. https://doi.org/10.1119/1.1522699
BCP measures where the ball makes contact with the bat, scaled from .00 (knob) to .99 (barrel end), making it the perfect metric to explore your bat’s “sweet spot,” where power meets precision. On a standard 34-inch bat, this zone often falls around .82–.88 BCP (Nathan, American Journal of Physics, 2003). Every bat is unique, so experiment with yours to discover its exact sweet spot.
Explore Your Bat's
Sweet Spot with BCP


Every session generates a unique Bat Contact Point (BCP) profile. By reviewing today’s minimum, maximum, and bar distribution, you can see exactly where contact occurred across your swings. This snapshot helps you visualize your contact range and pinpoint how the ball met the bat throughout the session.
Understand
Your BCP Today

BCP

Discover Your BCP
Consistency
Consistency is key to better hitting. With the 70% Range, you can compare today’s BCP distribution against previous sessions to see how often contact falls within a controlled zone. A tighter range signals repeatable mechanics, while shifts across days highlight opportunities for adjustment and growth.


Review how your exit velocity (EV) shifts based on contact location along the bat. Our AI report highlights the highest, lowest, and average EVs at different Bat Contact Points (BCP), helping you spot where your swing generates the most power, where it drops off, and where you’re most consistent.
EV Breakdown
Along the Bat



See how often you connect in the sweet spot launch angle range (8°–32°) at each BCP segment. Each segment’s count is paired with a shaded curve showing the total across all BCPs for context. This reveals not only where you’re making contact, but also how often those contacts produce optimal, game-ready results.
Sweet Spot
Count by BCP


Exit velocity, launch angle, and key numbers
Capture astonishing moments of impact with industry-leading AI visual algorithms providing the most accurate key data and captivating visualization of advanced scientific data for training.

Bat Path
Biomechanics
EV / LA / BCP


Exit Velocity,EV
Launch Angle, LA
Exit Velocity refers to the speed when the ball leaves the barrel during batting. Generally, the higher the exit velocity is, the better.

Bat Contact Point, BCP
Launch Angle refers to the angle between the trajectory of a batted ball and the horizon. Generally, there is an optimum range of launch angles which has a higher probability of being a hit. (about 15~35 degrees)
Bat Contact Points refer to the location on the bat where the ball makes contact during the swing. This is represented as a ratio from the knob to the far end of the barrel. Different bats may have different optimal BCP ranges for best performance.

Bat Path
Gain in-depth insights into your bat control and make informed adjustments.




Carry a collection of all your swings with you
Every perfect and imperfect swing is in your pocket, allowing you to review your progress anytime.
beyond brilliant batting breakdown

The innovative Immersive Pitch refines your timing and reaction speed down to the millisecond.


Stay tuned to your favorite athletes at all times
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