An amazing app called Displayout is available at the Cydia that allows you to mirror the screen of iPad to the external display via the composite or VGA cable.
It allows to do something that you could not do earlier on an iPad, that is create app videos. The app also allow you to adjust the refresh rate which can result in better video quality. However, keep in mind that higher refresh implies higher system resources (which means negative effect on the battery runtime). Available via Cydia.
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