Citrix has released a good Proof of Concept Implementation Guide for Citrix CloudGateway Express version 1.2

Citrix CloudGateway Express provides users with a common access experience across devices. Each CloudGateway Express user is able to subscribe to their favorite application and desktop resources, these favorite resources then automatically follow the user between devices. With Citrix Web Interface reaching end-of-life in 2015, it is important that administrators become familiar with CloudGateway Express to facilitate a successful transition between products.
CloudGateway Express’s new modular architecture improves upon the existing design of Web Interface. It includes a new user authentication method which directly queries Active Directory rather than the existing double-hop Web Interface process where user credentials are sent from the Web Interface server to the XML broker who then negotiates authentication with the Domain Controller. CloudGateway Express also makes the process of deploying multiple servers easier through its configuration synchronization feature.
Customers that require a single point of access and self-service for Windows, Web, and SaaS applications should utilize the Enterprise version of CloudGateway. CloudGateway Enterprise is a premium product that must be purchased. CloudGateway Express is a no-cost product that is freely available for download for Citrix XenDesktop and XenApp customers.

Click here to download the Citrix CloudGateway Express 1.2 Proof of Concept Implementation Guide