The publish menu currently just POSTs a json string representing the layout to jsonblob.com, and adds the hash that is returned to the location bar, so it's easy to share. For example:
I think it makes sense to incorporate pointer and touch event handling at this point, can you please open an issue for discussion? Here is an old issue in phosphor for reference: phosphorjs/phosphor#154.
Nice widget! If you want to rebase float-area on lumino we can add that to the external examples in the README