Thanks... We already have
Yes, "STRETCH" is our term used for "Fluid Any Size Responsive HTML5 Ads"
1. You can use the editor to start with a blank canvas to create a Responsive Creative or upload a photoshop file.
We are looking at other uploads as well.
2. Attach or select any of the Responsive Ad Formats you want for a Responsive Creative
They can be single HTML5, or one banner with these different 300x250, 160x600, 970x250 placement sizes.
They can be fixed sizes and just "swap" based on the placements from the 1st party or agency ad server ( e.g. DFP, DFA, etc..)
or even have transitions between them like in this case and this partner.
3. The GSAP libraries are accessible and hosted on our CDN so you can use them to manipulate them via our JS editor.
We are looking for feedback to make this better and will be working on this in 2016. It was really the first step for us.
4. Then with the fluid layout and all the elements in the responsive creative and the GSAP effects.
Let us know if you need anything more.