The AMP embed option provides completely valid AMP markup for mobile pages. As with the Seamless and Iframe embed options, the AMP embed code is fully responsive to ensure that your form looks great on any device.
The Accelerated Mobile Pages Project (AMP) is an open-source initiative to improve the performance of web contents and ads through a publishing technology known as AMP. Essentially, AMP pages can load more quickly on mobile devices than your typical webpage, and they provide an enhanced viewing experience more ideal for smaller screens. Check out our blog post to learn more.
<script async custom-element="amp-iframe" src="https://cdn.ampproject.org/v0/amp-iframe-0.1.js"></script>
For more information about the amp-iframe, please refer to the AMP Project article.