RacquetTune - String Tension

Name: RacquetTune - String Tension
Price: 2.99 USD
Rating: 4.6 (468 reviews)
Author: Sten Kaiser

By: Sten Kaiser

Racquet optimization tools

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Features & Capabilities

RacquetTune - String Tension is a Chrome extension that listens to the sound of strings to measure tension with high accuracy. It also provides a swingweight calculator and a stiffness calculator to help you tailor racquets to your stroke.

Designed for tennis, squash, racquetball, and badminton, RacquetTune tracks tension history, exports test data by email, and helps verify stringer consistency. View a demo at racquettune.com to see it in action.

User Growth & Download Statistics

App Sports Education

By:

Sten Kaiser

Rating:

4.60

(468)

Version:

7.7 Last updated: 2026-04-02

Version code:

884120241

Creation date:

2010-04-07

Compatible devices:

Size:

11.43MB

Price:

2.99

URLs:

Full description:

Source:

Apple Apps Store

Data ingested on:

2026-06-05

Compare stats and ranking:

Ranking

# 81,049 ▲ 45

Other rankings

#23 in Sports (Paid) ▼ 6#20 in string keyword 10 ▼ 2

For Developers

Monetize with App Pass Boost with Extension Booster

Contact the developer

Chrome-Stats does not own this Apple app. Please use these information below to contact the Apple app developer.

Developed by:

Sten Kaiser

Apple Apps Store

https://apps.apple.com/us/app/racquettune-string-tension/id365729342

User Reviews

Reviewers praise RacquetTune for tracking tension decay and serving as a useful reference, and some call it close to an industry standard for relative measurements. However, many reports cite inconsistent/incorrect absolute readings, reliability problems after updates, and a heavy reliance on correct string-factor calibration and database data. Support and UX concerns appear, making it a powerful but imperfect tool for stringing decisions.

Pros

Excellent for tracking tension loss over time with graphs and logs, helping plan restringing and monitor string wear
Readings can be relatively accurate and consistent enough to compare rackets and strings, serving as a practical reference
Useful for customizing rackets thanks to a database of strings and customizable string factors
Helpful instructions and an easy-to-read interface once set up, making it easy to use
Considered by many as a close to industry-standard tool for relative tension measurements

Cons

Absolute tension readings are often inconsistent or far from actual values, with large discrepancies between attempts
App reliability issues: measurements can stop, updates can break functionality, and support is reportedly lacking
User experience and setup can be non-intuitive; the app’s dependence on correct string factor and database data adds complexity
Need to calibrate string factor carefully for accuracy; online database can be hit-or-miss and misleads without personal calibration
Some users feel it’s not worth the price due to reliability issues and inconsistent results

Recent reviews

Hey Sten, would you please update the app? The app was still picking up my tapping before the 26.4 update. It's completely dead now.

by Lo*****, 2026-03-28

Great to understand how tension declines, not accurate but precise!. Keep notes on how it played and use the tension reported by the app as a reference. I use RPM Blast 17, pre-stretched 15 sec, strung at 55:53 and app reports 45.4, still very useful since these measurements are very consistent. I use this app now to keep a log of my string usage and tension. I recommend it!

by jo*****, 2025-05-28

The phone stopped measuring tension. No Support option to ask questions. There is discrepancy to the stringer and other stringing testing apps. Tends to measure below actual by 1-2 kg.