"Form-Based Composer for AP" is on the Adobe Target Future Roadmap However We are not sure of the date / timeline on when it will be available to the Adobe target Users.
Also,The at.js library is a new implementation library for Adobe Target designed for both typical web implementations and single-page applications.
Among other benefits, at.js improves page-load times for web implementations and provides better implementation options for single-page applications.
The at.js library offers several improvements over the mbox.js library, including:
Completely asynchronous communication via cross domain AJAX
Important: Although at.js communicates with the Target servers asynchronously, the at.js file itself must load synchronously in the <head> section of your page. Ideally, it should be one of the first scripts loaded. Once loaded, at.js executes mbox calls asynchronously through XMLHttpRequest, and does not block page rendering.
No more blocking calls
No document.write() used
Better timeout and error handling
Customizable timeout per call
No reloads on timeouts
Functions designed specifically for single-page apps/MVC frameworks