Microsoft recently clarified its stand on Sandbox solutions.
"While developing sandboxed solutions that contain only declarative markup and JavaScript -- which we call no-code sandboxed solutions (NCSS) -- is still viable, we have deprecated the use of custom managed code within the sandboxed solution."
Both NCSS(no-code sandboxed solutions) and app model can have only declarative markup and Javascript files. Is it safe to say that NCSS won't be of much value for a SharePoint 2013 farm configured for apps already? Are there any scenarios where you would prefer NCSS over app model?