Simplest keyboard manager useful for tablets with dock keyboards.
Start from the Launcher after installation to be workable.
This application opens the keyboard choose dialog each time you connect/disconnect your device to/from dock.
Use it to easily switch to your favorite on-screen keyboard when undocking and switch back to hardware keyboard when docking.
Also you can add a shortcut to the keyboard choosing dialog to your home screen or to the notification area.
Unfortunately this application cannot silently switch the keyboard for you. It's the Android security restriction which can be avoided only with root access. But this application doesn't require root.