# Music Theory by Justin Guitar

> How Music Works: Unlock guitar fretboard, chords & scales with JustinGuitar

Canonical page: [https://chrome-stats.com/d/net.musopia.theoryapp](https://chrome-stats.com/d/net.musopia.theoryapp)

## Overview

- **ID:** `net.musopia.theoryapp`
- **Platform:** Android
- **Type:** Android app
- **Status:** Available
- **Publisher:** Musopia
- **Category:** EDUCATION
- **Downloads:** 14,743
- **Rating:** 4.51 / 5 (239 ratings)
- **Version:** 1.0.5
- **Last updated:** 2026-09-17
- **First published:** 2025-10-06
- **Publisher country:** FI
- **Size:** 141 MB
- **Data as of:** 2026-09-24
- **Store listing:** [Google Play Store](https://play.google.com/store/apps/details?id=net.musopia.theoryapp)
- **Website:** [http://www.musopia.net](http://www.musopia.net/)
- **Privacy policy:** [https://www.musopia.net/privacy/](https://www.musopia.net/privacy/)

## Description

**Music Theory by Justin Guitar** helps guitarists understand music theory through practical, bite-sized lessons and interactive fretboard exercises. Learn notes, chords, scales, keys, intervals, chord progressions, barre chords, and fretboard patterns in a way that connects directly to playing acoustic or electric guitar.

Use fretboard and chord trainers, quizzes, and step-by-step exercises to improve note memorization, play by ear, write riffs and solos, and overcome practice plateaus. Created by Justin Sandercoe of JustinGuitar, the app supports learning at your own pace. Full access requires a subscription, and the app requires Android 15 or higher.

## Rankings

- #489,397 — Overall

## Permissions and access

### Permissions

- `android.permission.ACCESS_ADSERVICES_AD_ID`
- `android.permission.ACCESS_ADSERVICES_ATTRIBUTION`
- `android.permission.ACCESS_ADSERVICES_CUSTOM_AUDIENCE`
- `android.permission.ACCESS_ADSERVICES_TOPICS`
- `android.permission.ACCESS_NETWORK_STATE`
- `android.permission.BLUETOOTH`
- `android.permission.FOREGROUND_SERVICE`
- `android.permission.INTERNET`
- `android.permission.MODIFY_AUDIO_SETTINGS`
- `android.permission.POST_NOTIFICATIONS`
- `android.permission.RECEIVE_BOOT_COMPLETED`
- `android.permission.RECORD_AUDIO`
- `android.permission.WAKE_LOCK`
- `com.android.vending.BILLING`
- `com.android.vending.CHECK_LICENSE`
- `com.google.android.c2dm.permission.RECEIVE`
- `com.google.android.finsky.permission.BIND_GET_INSTALL_REFERRER_SERVICE`
- `com.google.android.gms.permission.AD_ID`
- `com.google.android.providers.gsf.permission.READ_GSERVICES`
- `net.musopia.theoryapp.DYNAMIC_RECEIVER_NOT_EXPORTED_PERMISSION`
- `net.musopia.theoryapp.permission.C2D_MESSAGE`

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Source: [Chrome-Stats](https://chrome-stats.com/d/net.musopia.theoryapp)