db4o is the open source object database that enables Java and .NET developers to store and retrieve any application object with only one line of code, eliminating the need to predefine or maintain a separate, rigid data model.

World class innovators deploy the db4o database engine at the heart of next generation data-driven devices and applications to cache user-generated and client-side data, enabling compelling new features and achieving unprecedented performance and flexibility.

db4objects offers the following products:

• db4o database runtime engine to be embedded and distributed with your products
• db4o Replication System (dRS) to sync db4o and relational backends
• ObjectManager Enterprise, a database visualizer and IDE plug-in for VisualStudio and Eclipse
• XtremeConnect expert support through live pairing

dDN Enterprise is the total package for professional product development with db4o's database engine.

Commercial or Free?

db4objects has dual-licensed db4o to offer you a choice between free and commercial depending on your needs.

The db4o engine is free when licensed under the General Public License (GPL) or distributed with non-GPL open source projects under the db4o Opensource Compatibility License (dOCL).
The db4o Community offers free developer resources incl. forums, documentation, and code samples.

A commercial license is required if you want to embed db4o in a non-GPL, commercial product and/or want to receive professional support.

For more guidance on licensing, please download this free whitepaper about db4objects' dual licensing model.