Actually, I missed the fact they released version 1.2 of Foundation for Apps 3 months ago. So there was a release, though the changes were small. The official Foundation for Apps site still shows “Install 1.1.0” sign - http://foundation.zurb.com/apps.html
In the changelog they write: “We’re planning a 1.3 release to transition between version 1.x and 2.x of Foundation for Apps.” -> http://foundation.zurb.com/apps/docs/#!/changelog
What I do personally, is I separate the grid features from Foundation for Apps (as they provide some great defaults for webapps which are not included in Sites) and use it together with Semantic UI.