TrueLine: Bowling Ball Tracker
Speed, hook & entry angle
Only for iPhone
Free · In‑App Purchases
iPhone
Pro-style ball tracking without the pro-shop price. Prop your phone behind the approach and get the numbers a coach would give you, on every single throw.
TrueLine turns your iPhone into a ball-motion tracker. Prop it behind the approach and bowl. Seconds after each throw, you see the numbers serious bowlers pay thousands to get, computed entirely on your phone.
WHAT IT MEASURES
• Ball speed
• Board at the arrows
• Launch angle
• Breakpoint board and distance
• Entry board and entry angle
• Total hook, in boards
• Pocket hits
SEE YOUR GAME
• Your throw replayed with the tracked path drawn on it
• Every line of a session fanned on one lane view
• Trends across sessions: speed, hook, entry angle, pocket %
• Compare your arsenal: per-ball speed, hook, and pocket rate
• Target-line practice: pick a board, get scored on hitting it
• Share cards: one tap turns any shot into a post-ready image
MADE FOR PRACTICE
• Calibrate once per phone placement, then just bowl
• Works at any center on any lane, no extra hardware needed
• Analyze footage you already have from your camera roll
PRIVACY
Everything runs on your iPhone. There is no account and no subscription, and nothing is ever uploaded anywhere. Your first 10 throws are free. A single purchase unlocks TrueLine forever.
The developer, ADAM CHENGER ZHU, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Collected
The developer does not collect any data from this app.
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- ADAM CHENGER ZHU
- Size
- 7.7 MB
- Category
- Sports
- Compatibility
Requires iOS 17.0 or later.
- iPhone
Requires iOS 17.0 or later. - Apple Vision
Requires visionOS 1.0 or later.
- iPhone
- Languages
- English
- Age Rating
4+
- 4+
- In-App Purchases
Yes
- TrueLine Unlimited $14.99
- Copyright
- © 2026 Adam Zhu