Recent news:
8.11.2013: Version 13.11 is released! This release simplifies flight configurations by replacing the dialog with the configuration tab. Motor filtering in the motor chooser dialog has been enhanced. Chineese translations have been added and Russian translations updated. Updated the 3D libraries, and squashed some bugs introduced by Java 1.7.0_45-b18.
6.10.2013: Version 13.09.1 is released! This is a bug-fix release, and includes updated 3D libraries and new thrust curves for Aerotech C3 and D2.
8.9.2013: Version 13.09 is released! This release contains numerous bug fixes, updated 3D JOGL libraries, and separated simulation edit and plot dialogs.
4.5.2013: Version 13.05 is released! This release contains a huge number of improvements, the main ones including realistic 3D rendering with decals, flight configurations, lower stage descent simulation, boosted dart support and new translations for Portuguese and Japanese. These are thanks to many contributors.
Version 13.05 also changes the file format to be ZIP-based. Versions earlier than 12.03 will not be able to read files saved by this version.
Ready packages
These are packages ready for use and are the recommended download for normal users. They are pre-packaged with motor thrust curves from thrustcurve.org.
OpenRocket requires Java version 6 or later. The Sun Java Runtime is recommended.
Desktop version
This is the latest version of the desktop version of OpenRocket. It contains the latest and greatest features, and runs on any system supporting Java.

OpenRocket can be started in most graphical environments (including Windows) by double-clicking the package icon. No installation is required.
From the command line OpenRocket can be started by java -jar OpenRocket-13.11.jar
Android version
The Android version allows opening OpenRocket files, viewing simulations and motors. Later versions will allow running simulations as well.
The Android version is thanks to the fantastic work by Kevin Ruland.

Installation:
- Go to Settings → Applications and check Unknown sources.
- Download OpenRocket-Android-12.09.apk on your device and accept installation.
Source code and older versions
Source packages and older versions of OpenRocket are available in the SourceForge repository.
Alternatively, the most recent development version can be obtained from GitHub. The code can be retrieved using the command
$ git clone git://github.com/openrocket/openrocket.git
The above URL may be used to connect to the repository with other Git clients as well.