We have android and iOS apps which are already showing Ad-Interstitials (using the Google DFP SDK) and want to show video-ads from a VAST-Tag inside of the interstitials. We need a HTML/JS creative for this interstitials which is compatible to MRAID (for e.g. closing the interstitial) but also VAST (to get the video source, tracking and so on).
Developing/testing should be easy, you need an iPhone/iPad or Android device and use e.g. the google provided interstitial demo app. You will get two things from us: The VAST-URL for the video-ads and an AdUnit-ID which needs to be placed in the Demo-App.
Requests to the AdUnit will be redirected to an URL you provide and use for development/testing. When you then trigger the intersitital in the demo-app the interstitial will render the URL you gave us. It should play a video provided by the VAST-URL.