The DocuSign API has a feature called "Embedded Sending", whereby you embed a DocuSign page in your app that allows the user to interactively place signature fields on the document to be signed, using a drag and drop interface.
https://www.docusign.com/developer-center/explore/features/embedding-docusign#EmbeddedSending
I've been reading the EchoSign documentation and trying to determine if this is possible with their API. The Widget functionality seems to allow embedding signing but I'm not sure you can use it to do embedding sending.
Does EchoSign allow anything like this?