The SDK includes a Widget emulator to allow developers to test their widgets on multiple devices. It will show how a widget will appear on a TV, computer and mobile screen and is intended to make cross-device development easier. There's also a set of libraries available for adding animation and other characteristics to widget applications. Also bundled with the SDK is Opera Dragonfly. Opera Dragonfly is a recently announced developer tool designed to help with debugging of web technology implementations. The SDK also includes documentation and access to forums for support.
Here are a few example screenshots of how Opera Widgets would appear on a UIQ 3.3 device.