# PSI Tennis App — A Tennis Tracking App > Tennis performance analysis app with statistical grading for players. (iPhone/iPad app by Court 9, LLC.) - Source: https://appshunter.io/ios/app/psi-tennis-app/id1578695961 (this page in markdown: same URL + `.md`) - Developer: [Court 9, LLC](https://appshunter.io/developer/1577177361) - Category: Sports, Utilities - Price: Free with in-app purchases - Rating: 5.00/5 from 4 App Store ratings · 1 written reviews indexed - Age rating: 4+ - Requires: iOS 12.0 · 50 MB - Languages: English - Released: 2022-01-04 - Data updated: 2026-08-19 - Monetization: free with in-app purchases - User reviews in markdown: https://appshunter.io/ios/app/psi-tennis-app/id1578695961/reviews.md ## What is PSI Tennis App? The Performance Stat Index (PSI) was first introduced in 2009 in the form of a workbook for players on the ATP Challenger circuit to make them aware of strengths and weaknesses as well as get an overall view of their performance. Two more indexes were later added to the PSI for players in the intermediate and more advanced player range right below the highest level Index used on the ATP Challenger circuit. Index 1: players with UTRs 3-6.99 Index 2: players with UTRs 7-10.99 Index 3: players with UTRs 11+ A statistical algorithm adds up the total RATIO DIFFERENCE of WON (Good Shots) to LOST (Bad Shots) points in a set. The algorithm then calculates to find the AVERAGE of points either won or lost PER GAME in the set. We refer to these average numbers of points as PSI Ratings. Good Shots = Unreturned Serves, Winners, Forced Errors Bad Shots = Double Faults, Unforced Errors, Missed Makeable Shots After a set is played, both players receive PSI Ratings. If the player’s final PSI Ratings are positive, it means they won more points than lost. If the player’s final PSI Ratings are negative, it means they lost more points than won. At the core of the app are the three indexes that ultimately bestow the PSI GRADES. Three areas of a player’s performance are graded within each designated Index; SERVICE PERFORMANCE, GROUNDSTROKE AND AUXILIARY, and OVERALL PERFORMANCE. All areas consist of uniformed parameters of Good Shot/Bad Shot point averages that make up each Index established through years of research of charting competitive matches at all levels of the game. The following are the PSI PERFORMANCE GRADES. Excellent Performance Above Average Performance Solid Performance Below Average Performance Poor Performance Because the total number of shots recorded can fluctuate, ratios can vary from a 1 to 1.1 ratio to a 1 to 1.9 ratio and so on. A point of reference (midpoint) and closest to Index 2 OVERALL PERFORMANCE parameters is this example. Excellent Performance 3 Good Shots to 1 Bad Shot Ratio Above Average Performance 2 Good Shots to 1 Bad Shot Ratio Solid Performance 1 Good Shot to 1 Bad Shot Ratio Below Average Performance 1 Good Shot to 2 Bad Shot Ratio Poor Performance 1 Good Shot to 3 Bad Shot Ratio Index 1 will have a lower threshold to Solid. Index 3 will have a higher threshold to Solid. Terms of Use EULA: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ ## Key features - Performance Stat Index (PSI) analysis - Breakdown of strengths and weaknesses - Graded performance metrics - Tailored indexes for different player levels - Statistical algorithm for point analysis - Good Shot/Bad Shot ratio tracking ## Pricing and in-app purchases Base price: Free. **Subscriptions** | Subscription | Price | Period | | --- | --- | --- | | Monthly Subscription | $3.99 | per month | ## Recent user reviews (1 of 1) All indexed reviews: https://appshunter.io/ios/app/psi-tennis-app/id1578695961/reviews.md ### 5/5 — The best app that tennis have to measure performance *2022-01-20* I have two college players and one professional player and I enjoy keeping track of their performance. Love the app and they love it too. ## Frequently asked questions about PSI Tennis App ### What is the PSI Tennis App? The PSI Tennis App is a tool designed to provide detailed performance analysis for tennis players. It uses a statistical algorithm to break down player performance into strengths and weaknesses across various aspects of the game. ### How does the PSI Tennis App calculate performance? It calculates performance by analyzing the ratio of 'Good Shots' (like winners and unreturned serves) to 'Bad Shots' (like double faults and unforced errors) within a set. This data is then used to generate PSI Ratings and Grades. ### Are there different levels of analysis in the PSI Tennis App? Yes, the app features three distinct indexes tailored for players with different UTR ranges: Index 1 (UTR 3-6.99), Index 2 (UTR 7-10.99), and Index 3 (UTR 11+). ### What performance areas does the PSI Tennis App grade? The app grades three key areas: SERVICE PERFORMANCE, GROUNDSTROKE AND AUXILIARY, and OVERALL PERFORMANCE, providing a comprehensive view of a player's game. ### Is the PSI Tennis App free to use? The PSI Tennis App is free to download and use. It offers a monthly subscription at $3.99, which includes a 1-month free trial. ### What devices is the PSI Tennis App compatible with? The PSI Tennis App is currently supported on iPhone and iPod devices. ### How often is the PSI Tennis App updated? The app was last updated on February 12, 2024, with version 1.3.3. This indicates regular maintenance and potential feature additions. ### What is the user sentiment for the PSI Tennis App? Based on the available data, the PSI Tennis App has a perfect rating of 5.0 stars from 4 ratings, suggesting a very positive user reception. ## Version history (last 3 releases) ### 1.3.3 — 2024-02-12 New Add Notes feature for every matches. ### 1.0.1 — 2022-01-08 Improved subscription purchasing experience. ### 1.0 — 2022-01-04 No release notes. --- *Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-08-19.*