OpenMTP | Android File Transfer for macOS

Author: Ganesh Rathinavel
License: MIT
System Requirements: macOS 11.0 (Big Sur) or higher
Website URL: https://openmtp.ganeshrvel.com
Repo URL: https://github.com/ganeshrvel/openmtp
Contacts: ganeshrvel@outlook.com

Introduction

Advanced Android File Transfer Application for macOS.

Transferring files between macOS and Android or any other MTP devices has always been a nightmare. There are a few File Transfer MTP apps which are available online but most of them are either too expensive or come with bad UI/UX. The official "Android File Transfer" app for macOS from Google comes with bugs, innumerable limitations, some of which include - not being able to transfer files larger than 4GB, frequent disconnections, unable to rename the folders or files on the android/MTP devices. Most of the other apps available online uses either WiFi or ADB protocol to transfer the files, which is an extremely time-consuming process.

Countless searches to find an app to solve these problems and failing to find one made me restless. So, I took the leap and decided to create an app for us that could help us have a smooth and hassle-free file transfer process from macOS to Android/MTP devices. Created with the objective of giving back to the community, we can all use this app for free in this lifetime.

Features

Safe, Transparent and Open-Source
Plug and Play via USB. No hassles, easy and instant connection.
Select between Internal Memory and SD Card
Transfer multiple files which are larger than 4GB
Dark mode
Drag-and-drop support
Split pane views for both Local Computer and Android device
Choose between Grid and List view.
Use Keyboard Shortcuts to navigate through your files.
No collection of personally identifiable information.

Kalam Kernel

OpenMTP 3.0 features a new MTP kernel and it was written from the scratch. It promises a file copy speed of 30 to 40 MB/s on low and mid range devices and 100 to 120 MB/s on higher end devices. The all new and powerful MTP kernel is named after Dr. A. P. J. Abdul Kalam

Do checkout the Go package which I've written to build Kalam Kernel: github.com/ganeshrvel/go-mtpx. Feel free to raise PRs.

System Requirements and Support

To support macOS version below Big Sur the Kalam kernel needs to be compiled on an older macOS machine everytime there is an update, which is practically very difficult
Only the latest 3 versions of macOS will receive the Kalam Kernel updates, which includes new device supports, fixes, stability improvements. macOS Big Sur (11.0) or above will receive the above said updates
We have now officially retired the support for Kalam Kernel on macOS 10.13 (OS X El High Sierra) and lower. Only the "Legacy" MTP mode will continue working on these outdated machines.
We will continue releasing the updates for both Intel and ARM64 machines

Installation

Download the Mac Apple Silicon version
Download the Mac Intel Silicon version
Using Homebrew Cask

  # newer versions:
  brew install openmtp --cask
  # older versions:
  brew cask install openmtp

Find the latest dmg file from GitHub Releases

Screengrabs

Keyboard Shortcuts

Command	Keyboard Shortcut
Delete	`backspace`
New Folder	`command (⌘)`+`n`
Copy	`command (⌘)`+`c`
Copy to Queue	`command (⌘)`+`shift`+`c`
Paste	`command (⌘)`+`v`
Refresh	`command (⌘)` +`r`
Folder Up	`command (⌘)`+`b`
Select All	`command (⌘)`+`a`
Rename	`command (⌘)`+`d`
Switch Tab	`command(⌘)`+`1`
Open	`enter`
Navigate Left	`left`
Navigate Right	`right`
Navigate Up	`up`
Navigate Down	`down`
Select Multiple Items Forward (in Grid View)	`shift`+`left`
Select Multiple Items Backward (in Grid View)	`shift`+`right`
Select Multiple Items Forward (in List View)	`shift`+`up`
Select Multiple Items Backward (in List View)	`shift`+`down`
Select Multiple Items (with mouse)	`command (⌘)`+`click` or `shift`+`click`

Building from Source

Requirements: Node.js v10, Git and Yarn package manager

Clone

$ git clone https://github.com/ganeshrvel/openmtp.git

$ cd openmtp

# install yarn
npm install -g yarn

# install sentry cli
npm -g i @sentry/cli

$ yarn

Run

A fresh clone might throw undefined state error. Run the following commands once to fix the issue.

# For Mac and Linux
$ UPGRADE_EXTENSIONS=1 npm run dev

# For Windows
$ set UPGRADE_EXTENSIONS=1 && npm run dev

# Development
$ yarn dev

# Pre-production
$ yarn start

Debugging a Packaged app

# On terminal run
$ "/path/to/OpenMTP.app/Contents/MacOS/OpenMTP" --remote-debugging-port=6363

Open a Chromium browser
Input "about://inpsect" into the URL bar
Add a new connection localhost:6363
Inpect OpenMTP @ port 6363

Publishing using CI/CD:

CodeMagic.io
- Create a new App (Choose others -> Enter Electron)
- Environment variables:
  - APPLEID: <Apple developer account username>
  - APPLE_APP_SPECIFIC_PASSWORD: <App-Specific Password>
    - Log into your Apple Account
    - Goto Sign-In and Security > App-Specific Passwords
    - Click on Generate Password..., enter a password label and click Create
    - Copy the displayed app-specific-password
  - SENTRY_URL: https://sentry.io/
  - SENTRY_ORG: <Sentry Organization Name>
  - SENTRY_PROJECT: <Sentry Project>
  - SENTRY_TOKEN_ID: <Sentry Auth Token>
    - Find it from here: Auth Tokens
    - Scopes: event:admin, event:read, member:read, org:read, project:read, project:releases, team:read
  - GITHUB_TOKEN: Personal access token
    - Find it from here: Personal access tokens
    - Scopes: admin:gpg_key, admin:public_key, repo, user, workflow
  - CSC_LINK:
    - Keychain -> Default Keychains menu in the left -> Login -> My Certificates
    - Search for Developer ID Application in the top search bar
      - If there are no results for the Developer ID Application, for the organization, create one from here: Apple Developer Certificates
      - Follow these steps to get the Apple Developer certificated installed in the local machine Obtaining-an-Apple-Developer-ID-Certificate-for-macOS-Provisioning
    - Search for Developer ID Application in the top search bar
    - Expand Developer ID Application: <User Name> (XXXYYYZZZ)
    - See if the private key's name matches this: Mac Developer ID Application: <User Name>
      - Else rename the private key as (right click -> get info) Mac Developer ID Application: <User Name>
      - Close the window
    - Right Click on the private key -> Mac Developer ID Application: <User Name>
    - Export Mac Developer ID Application: <User Name>
    - File name: CERTIFICATE_PRIVATE_KEY.p12
    - Enter Password. This is the CSC_KEY_PASSWORD, note this down
    - Run (this step doesnt work if you are using fig or ohmyzsh, use raw terminal):
      - base64 -i CERTIFICATE_PRIVATE_KEY.p12 -o CERTIFICATE_PRIVATE_KEY.txt
    - Copy the whole content of the file CERTIFICATE_PRIVATE_KEY.txt
    - Paste the content as the value for the field CSC_LINK
  - CSC_KEY_PASSWORD is the password from the above step
  - CODEMAGIC_AUTH_TOKEN_ID: <CodeMagic API Token>
    - Find it from here: Sidebar -> Teams -> Personal Account -> Integrations -> Codemagic API
  - CODEMAGIC_INTEL_X64_WORKFLOW_ID_PROD: <Prod codeMagic workflow id>
    - Find the relevant workflow id from codemagic.yaml, (mostly macos-intel-x64-build-prod)
  - CODEMAGIC_INTEL_X64_WORKFLOW_ID_DEV: <Dev codeMagic workflow id>
    - Find the relevant workflow id from codemagic.yaml, (mostly macos-intel-x64-build-dev)
  - PUBLISH_PROD_REPOSITORY: <Repository to publish the production app>
  - PUBLISH_DEV_REPOSITORY: <Repository to publish the dev app>
  - CODEMAGIC_PUBLISH_PROJECT_ID: <Codemagic intel project id>
  - PUBLISH_EMAIL: Email address to receive the updates on publish
  - References:
    - https://www.electron.build/code-signing.html
    - https://docs.codemagic.io/yaml-code-signing/signing-macos/#saving-the-api-key-to-environment-variables

Packaging (locally) and Publishing

Setup the code signing to build, package (locally) and publish the app.

App Notarization for macOS (skip this section for non macOS builds)

Rename sample.env file as .env
To update APPLEID and APPLE_APP_SPECIFIC_PASSWORD in .env file
Log into your Apple Account
Goto Sign-In and Security > App-Specific Passwords
Click on Generate Password..., enter a password label and click Create
Copy the displayed app-specific-password
Run

security add-generic-password -a "<apple-developer-account-username>" -w <app-specific-password> -s "APPLE_APP_SPECIFIC_PASSWORD"

Log into your Apple App Store Connect Account and accept the presented terms and conditions
The statuses shall turn Active

Sentry

Auth Tokens Settings page: https://sentry.io/settings/account/api/auth-tokens/

npm install -g @sentry/wizard
sentry-wizard --integration electron

# Upload Debug Information
# Everytime the electron.js version is upgraded run:
node sentry-symbols.js

sentry-cli login

Packaging Instructions: https://www.electron.build/code-signing

$ export GH_TOKEN="<github token>"

# For local platform
$ yarn package

# For multiple platforms
$ yarn package-all

Technical Features

Built using Electron v17 and React v18
Loadables, Dynamic Reducer Injection, Selectors for code splitting and performance optimization
Hot module reload (HMR) for instant feedback
Inbuilt error logging and profile/settings management
Industry standard state management
JSS, SASS/SCSS styling
Port assigned: 4642

Configurations

config/env/env.dev.js and config/env/env.prod.js contain the PORT number of the app.
config/dev-app-update.yml file holds the GitHub repo variables required by electron-updater.
config/google-analytics-key.js file contains the Google Analytics Tracking ID.
package.json build.publish object holds the values for publishing the packaged application.
app/constants folder contains all the constants required by the app.

Debugging

Debugging Guide

electron-react-boilerplate/electron-react-boilerplate#400

Dispatching redux actions from the main process

electron-react-boilerplate/electron-react-boilerplate#118

electron-react-boilerplate/electron-react-boilerplate#108

VM112:2 Uncaught TypeError: Cannot read property 'state' of undefined error

# For Mac and Linux
$ UPGRADE_EXTENSIONS=1 npm run dev

# For Windows
$ set UPGRADE_EXTENSIONS=1 && npm run dev

Troubleshooting

Your device is not recognized

node-mac-permissions throws `Speech framework is not compatible with macOS < 10.15`

On macOS <= 10.14.x (mojave) the yarn install will throw a npm-rebuild error
To "test" or "debug" the app on macOS mojave:
- remove the node-mac-permissions dependency from package.json
- Add the ignorePlugin line to default.plugins in the file webpack/config.base.js
  - new webpack.IgnorePlugin({ resourceRegExp: /^(node-mac-permissions)$/u }),
- WARNING: DO NOT commit these changes to the upstream!!
The NODE_MAC_PERMISSIONS_MIN_OS constant defines the minimum os version that is required to show the macos usage access permission popup
For distribution make sure to build the app on a machine which is at least 10.15 (Catalina)

https://stackoverflow.com/questions/58358449/notarizing-electron-apps-throws-you-must-first-sign-the-relevant-contracts-on

Raise an issue if your device is undetected: https://github.com/ganeshrvel/openmtp/issues/new?template=contribute.md

The app goes blank while trying to connect a Samsung device

Uninstall Samsung SmartSwitch, if installed: https://farazfazli.medium.com/how-i-reverse-engineered-keis-and-sidesync-and-fixed-mtp-8949acbb1c29, ganeshrvel#212.

Notarizing Electron apps throws - “You must first sign the relevant contracts online. (1048)” error