Port21

Port21 is a modern FTP client application built with Flutter for Android. It supports standard FTP as well as secure FTPS connections.

Features

• Protocol Support:
  • FTP: Standard File Transfer Protocol.
  • FTPS: FTP over TLS (Implicit/Explicit) for secure transfers.
• File Management:
  • Browse files and directories.
  • Upload files from local storage.
  • Download files to the device (Downloads folder).
  • Delete files remotely.
• Responsive UI: Designed to work on phones and tablets.

Getting Started

Prerequisites

• Flutter SDK
• Android SDK
• Java 21 (JDK 21) or compatible LTS version.

Installation

1. Clone the repository.
2. Install dependencies:

   flutter pub get

3. Run the app:

   flutter run

Troubleshooting: Java Warnings or Build Errors

If you encounter warnings like WARNING: A restricted method in java.lang.System has been called or build errors related to Java version:

1. Java Version: Ensure you are using Java 21 (JDK 21). Java 25 is currently too new for some Gradle components.
2. Fix: Set JAVA_HOME to your Java 21 installation before running Gradle:

   export JAVA_HOME=/usr/lib/jvm/java-21-openjdk-amd64
   ./gradlew run

Features added in v1.1

• Upload Progress: Real-time progress bar and percentage during file uploads.
• Speed Indicator: Shows current upload speed (e.g., MB/s).
• Smart Permissions: Storage permissions are requested only when needed (on download), not at startup.
• Quick Connect: Saved profiles connect directly with one tap. Use the Edit icon to modify details.

Usage

1. Connect: Launch the app and enter your FTP server details (Host, Port, Username, Password).
2. Secure Mode: Toggle "Use FTPS (Secure)" for TLS connections.
3. Browse: Tap folders to navigate. Use the .. item to go up a directory.
4. Actions:
   • Upload: Tap the floating action button (+).
   • Context Menu: Tap the "more" (three dots) icon on a file to Download or Delete it.