String GOAT - for tennis

Contains adsIn-app purchases
39 reviews
Content rating
Everyone
10K+
Downloads
Content rating
Everyone
In-App Purchases
Learn more
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About this app

String GOAT is the all-in-one tennis string tracker for players and stringers. Your tennis strings lose tension every day, and String GOAT tells you when it's time to restring. Log every restring, track your tennis sessions with Apple Watch or Galaxy Watch, watch your string's predicted lifespan, and get AI string recommendations built on your own play data. Measured DT (dynamic tension) goes into the same record, alongside the strokes your watch counted.

KEY FEATURES

■ Apple Watch & Galaxy Watch
• Start a session right from your watch, with stroke count, heart rate, and calories tracked automatically
• Wear it on the wrist opposite your racket hand and strokes are counted automatically once a session starts
• GPS route and distance for outdoor sessions
• Sessions save to your phone automatically, even when you finish offline

■ DT & Tennis String Tension Tracking
• Log DT (dynamic tension, a measure of string bed stiffness) and tension readings, and enter the initial DT when you string
• Cumulative strokes up to each reading, overlaid on the DT chart
• Tension loss (%) from the initial value shown in stages, with settling loss kept separate when the baseline was measured on stringing day
• Tension history graph (mains vs. crosses)
• String type distribution and per-racket analysis

■ Know When to Restring
• Predicted string lifespan based on your actual play time
• Replacement reminders driven by real usage, not just the calendar
• Home screen widget shows string status and replacement urgency at a glance

■ Workout Journal
• Session list, details, and calendar view
• Heart rate zones and session statistics

■ String & Racket Management
• Full racket specs: brand, model, head size, weight, swingweight, balance, grip size, stiffness (RA), strung weight and balance
• String setup: brand, model, type, shape, tension, gauge
• Hybrid stringing support (separate mains & crosses)
• String pattern, knots, pre-stretch (mains/crosses %), overgrip
• Stringing machine registry (electronic, drop weight, crank)
• Racket detail page with per-racket string history and stats

■ Tennis String Inventory
• String reels and sets, plus overgrips, grips, lead tape and butt caps
• Stock deducted automatically when you log a job
• Alerts before stock runs out

■ Performance Feedback
• Rate 6 key areas: Power, Spin, Control, Comfort, Feel, Durability
• Add detailed comments for each category

■ Stringer Mode & Customer Management (Premium)
• Rackets and tennis string job history for each customer
• Work queue with pickup dates and rackets awaiting pickup
• Labor and string cost, revenue calendar, customer stats
• Pre-cut DT when you cut out a customer's strings
• Manage the same customer data on the web dashboard

■ AI String Lab
• AI string recommendations based on your records and feedback
• Hybrid string combo suggestions
• Tension advisor tailored to your stringing history
• AI chat for personalized stringing advice

■ Cloud Sync & Backup
• Sync across devices, with web dashboard access
• Cloud backup and restore
• Export your records to Excel

It works as a tennis string tracker, a string tension tracker, a racket and stringing log, and an AI-powered string recommendation tool, on your phone, your smartwatch, and the web.

SUBSCRIPTION PLANS

• Free: 1 racket, unlimited string records, inventory, 10 AI analyses/month, 8 watch session detail views/month
• Pro: unlimited rackets, 500 AI analyses/month, hybrid combination recommendations, unlimited watch session detail views, cloud sync & backup, web dashboard, Excel export, no ads
• Premium: everything in Pro + customer management (Stringer Mode), 1,000 AI analyses/month

Subscriptions are billed monthly or yearly. Payment is charged to your Google Play account. Subscriptions auto-renew unless canceled at least 24 hours before the end of the current period.
Tennis string log for stringers: DT tension, watch stroke count, stock & clients
Updated on
Sep 28, 2026

Data safety

Safety starts with understanding how developers collect and share your data. Data privacy and security practices may vary based on your use, region, and age. The developer provided this information and may update it over time.
  • This app may share these data types with third parties
    Location, App activity and 2 others
  • This app may collect these data types
    Location, Personal info and 6 others
  • Data is encrypted in transit
  • You can request that data be deleted

Ratings and reviews

38 reviews
Matt Sharpe
April 18, 2023
You only can save 2 strings for free. Otherwise it's $30. Seems excessive for such a basic app. I'd pay maybe $5-7.
1 person found this review helpful
Did you find this helpful?
String GOAT
April 19, 2023
Hello Matt Sharpe, I'm sorry you faced inconvenience with my app. Despite its simple appearance, I spent over a year developing it to ensure its functionality and user-friendliness. I'm aware of the pricing issue and have resolved it in the updated version. Thanks for notifying me, and please contact me if you have other concerns or suggestions.
P M (Phil)
July 4, 2025
Pretty and functional. Unfortunately this app limited itself to 2 string jobs. So on this basis - a bit of a waste of time as you can't use the features based on that.
Did you find this helpful?
String GOAT
May 6, 2026
Hi Phil, thank you for the feedback! We've listened to users like you and updated our policy. Now, free users can register and manage unlimited string jobs for one racket at no cost. We recently launched our website, https://stringgoat.com, for even easier tracking. We hope this makes the app much more useful for you! Happy hitting!
Sun Jin Kim
December 2, 2024
Awesome app. It's a great way to keep track of the racket strings for our family.
Did you find this helpful?
String GOAT
May 6, 2026
Hello Sun Jin Kim, thank you for the wonderful review! We're glad String GOAT helps manage your family's rackets. We've recently launched our website, https://stringgoat.com. Now you can view and manage your records even more comfortably on a larger screen. We'll keep working to make it the best tool for your family. Happy hitting!

What’s new

• With notifications on, we'll remind you 3 days before your trial ends
• Get a reminder before your first-record Premium Bonus ends
• Fixed locked features showing the upgrade screen when your first-record Premium Bonus hadn't reached the app yet
• Premium Bonus end reminders no longer appear if you already subscribe
• The Stringer Mode suggestion now also appears during your Premium Bonus
Content rating
Everyone
In-App Purchases
Learn more

App support

About the developer
윤요섭
stringgoat.dev@gmail.com
센트럴타운로22번길 36 영통구, 수원시, 경기도 16505 South Korea