# Number System Trainer — Nashville Number System > Interactive music app for learning and mastering the Nashville Number System. (iPhone/iPad app by Brandon Oaks.) - Source: https://appshunter.io/ios/app/number-system-trainer/id6786437503 (this page in markdown: same URL + `.md`) - Developer: [Brandon Oaks](https://appshunter.io/developer/6786437505) - Category: Music, Education - Price: Free - Rating: 5.00/5 from 10 App Store ratings · 7 written reviews indexed - Age rating: 4+ - Requires: iOS 15.0 · 10 MB - Languages: American English - Released: 2026-07-07 - Data updated: 2026-09-01 - Monetization: free with in-app purchases - User reviews in markdown: https://appshunter.io/ios/app/number-system-trainer/id6786437503/reviews.md ## What is Number System Trainer? Number System Trainer teaches you the Nashville Number System — the method worship musicians and session players use to learn songs fast, transpose on the fly, and communicate with any musician in any key. Whether you're a beginner who only knows 3 chords or an experienced worship leader, this app meets you where you are. 6 INTERACTIVE MODULES • Learn — A 5-step intro to how the number system works • Read Charts — 4 levels from basic chords to slash chords • Transpose — Move full progressions to any key instantly • Ear Training — 3 levels, identify chords just by listening • Play Along — See piano and guitar shapes in every key, with capo tips built in • Circle of 4ths & 5ths — Tap any key to see all 7 chords No login required. Works instantly. ## Key features - Interactive learning modules - Chord reading and identification - Instant transposition - Ear training exercises - Visual chord shapes - Circle of 4ths & 5ths reference ## Recent user reviews (7 of 7) All indexed reviews: https://appshunter.io/ios/app/number-system-trainer/id6786437503/reviews.md ### 5/5 — Great app! Very helpful! *2026-07-21* If you or someone on your team needs help learning and understanding the number system, get this app and play with it. Full of information that will help you make sense of the numbers. Great for worship leaders, band members, young and old. ### 5/5 — Must Have *2026-07-21* This app is crazy creative! A must have for every worship leader! ### 5/5 — Its so tuff *2026-07-18* Its so tuff ### 5/5 — every worship leader needs this! *2026-07-10* No other app like this out there!! Super convenient and easy way to learn the Nashville Number System. every worship leader should have this app! ### 5/5 — You’ll be playing your favorite songs in no time. *2026-07-10* It is so easy to use and allows me to play songs in any key. ### 5/5 — Game changer!! *2026-07-10* Awesome app! Super easy to understand! This has helped make learning songs and training your ear much easier! Wether you are a beginner or a wanting to sharpen you ear, this is the app for you! ### 5/5 — 10/10 *2026-07-08* It was a great app and I learned so much from it! I would recommend this app to every worship leader out there. 10/10 ## Frequently asked questions about Number System Trainer ### What is the Nashville Number System? The Nashville Number System is a method used by musicians to learn songs quickly, transpose on the fly, and communicate chord progressions. It uses numbers to represent chords in relation to the key, making it universally understandable. ### Who is Number System Trainer for? Number System Trainer is designed for musicians of all levels, from beginners who know a few chords to experienced worship leaders and session players. It helps anyone looking to master the Nashville Number System. ### Does Number System Trainer have ads? No, Number System Trainer does not contain advertisements. It offers a clean, ad-free learning experience for users. ### How often is Number System Trainer updated? The app was last updated on July 21, 2026, with version 1.1.1. This indicates recent development and potential for future updates based on user feedback and new features. ### What devices support Number System Trainer? Number System Trainer is available for iPhone, iPad, and iPod devices, making it accessible to a wide range of Apple users. ### Is Number System Trainer suitable for young learners? Yes, Number System Trainer has an age rating of 4+, making it appropriate for younger users interested in learning music fundamentals. ### Can I use Number System Trainer offline? The app description states 'Works instantly' and 'No login required,' suggesting that core functionalities are available offline, allowing for practice anytime, anywhere. ### What are the interactive modules in Number System Trainer? The app features six interactive modules: Learn, Read Charts, Transpose, Ear Training, Play Along, and Circle of 4ths & 5ths, covering various aspects of the Nashville Number System. ## Version history (last 3 releases) ### 1.1.1 — 2026-07-21 Bug fix: purchases now unlock reliably on every launch ### 1.1 — 2026-07-13 In App Purchases ### 1.0 — 2026-07-07 No release notes. ## Related topics [nashville numbers](https://appshunter.io/ios/topics/nashville-numbers) · [music number wheel](https://appshunter.io/ios/topics/music-number-wheel) --- *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 2026-09-01.*