aCal: an Android CalDAV Client
aCal CalDAV Client is a project by Andrew McMillan to create a straightforward Android CalDAV client for shared groupware calendaring.
Visit the aCal wiki for more detailed information about this project.
Getting the App
The app is currently in the Android Market for roughly $2.00, depending on your currency.
Getting the Code
The code has been published to the aCal Git repository on Gitorious.
In the first instance have a look around the aCal wiki. There's specific information on there for configuring aCal to work with a variety of CalDAV servers we've tested it against.
There are two aCal mailing lists that you could subscribe to, and at present this is the best place for you to report bugs.
Take a look at the latest commits to aCal on Gitorious to get an idea of where the project is heading.