Citrix Virtual Apps and Desktops

Delivery methods

Citrix Virtual Apps and Desktops offers various delivery methods. A single delivery method will likely not meet all of your requirements.


Choosing the appropriate application delivery method helps improve scalability, management, and user experience.

  • Installed app: The application is part of the base desktop image. The install process involves dll, exe, and other files copied to the image drive, in addition to registry modifications. For details, see Create machine catalogs.
  • Streamed app (Microsoft App-V): The application is profiled and delivered to the desktops across the network on demand. Application files and registry settings are placed in a container on the virtual desktop and isolated from the base operating system and each other. This isolation helps address compatibility issues. For details, see App-V.
  • Layered app (Citrix App Layering): Each layer contains a single application, agent, or operating system. By integrating one OS layer, one platform layer (VDA, Citrix Provisioning agent) and many application layers, an administrator can easily create new, deployable images. Layering simplifies ongoing maintenance, as an OS, agent, and application exists in a single layer. When you update the layer, all deployed images containing that layer are updated. For details, see Citrix App Layering.
  • Hosted Windows app: An application installed on a multi-user Citrix Virtual Apps host and deployed as an application and not a desktop. A user accesses the hosted Windows app seamlessly from the VDI desktop or endpoint device, hiding the fact that the app is executing remotely. For details, see Create delivery groups.
  • Local app: An application deployed on the endpoint device. The application interface appears within the user’s hosted VDI session, even though it executes on the endpoint. For details, see Local App Access and URL redirection.

For desktops, consider published desktops or VDI desktops.

Citrix Virtual Apps published apps and desktops

Use multi-session OS machines to deliver Citrix Virtual Apps and Desktops published apps and published desktops.

Use case:

  • You want inexpensive server-based delivery to minimize the cost of delivering applications to many users, while providing a secure, high-definition user experience.
  • Your users perform well-defined tasks and do not require personalization or offline access to applications. Users can include task workers such as call center operators and retail workers, or users that share workstations.
  • Application types: any application.

Benefits and considerations:

  • Manageable and scalable solution within your data center.
  • Most cost effective application delivery solution.
  • Hosted applications are managed centrally and users cannot modify the application. This provides a user experience that is consistent, safe, and reliable.
  • Users must be online to access their applications.

User experience:

  • User requests one or more applications from StoreFront, their Start menu, or a URL you provide.
  • Applications are delivered virtually and display seamlessly in high definition on user devices.
  • Depending on profile settings, user changes are saved when the user’s application session ends. Otherwise, the changes are deleted.

Process, host, and deliver applications:

  • Application processing takes place on hosting machines, rather than on the user devices. The hosting machine can be a physical or a virtual machine.
  • Applications and desktops reside on a multi-session OS machine.
  • Machines become available through machine catalogs.
  • Machines from machine catalogs are organized into delivery groups that deliver the same set of applications to groups of users.
  • Multi-session OS machines support delivery groups that host either desktops or applications, or both.

Session management and assignment:

  • Multi-session OS machines run multiple sessions from a single machine to deliver multiple applications and desktops to multiple, simultaneously connected users. Each user requires a single session from which they can run all their hosted applications.

    For example, a user logs on and requests an application. One session on that machine becomes unavailable to other users. A second user logs on and requests an application which that machine hosts. A second session on the same machine is now unavailable. If both users request more applications, no additional sessions are required because a user can run multiple applications using the same session. If two more users log on and request desktops, and two sessions are available on that same machine, that single machine is now using four sessions to host four different users.

  • Within the delivery group to which a user is assigned, a machine on the least loaded server is selected. A machine with session availability is randomly assigned to deliver applications to a user when that user logs on.

VM hosted apps

Use single-session OS machines to deliver VM hosted applications

Use case:

  • You want a client-based application delivery solution that is secure, provides centralized management, and supports many users per host server. You want to provide those users with applications that display seamlessly in high definition.
  • Your users are internal, external contractors, third-party collaborators, and other provisional team members. Your users do not require offline access to hosted applications.
  • Application types: Applications that might not work well with other applications or might interact with the operation system, such as Microsoft .NET Framework. These types of applications are ideal for hosting on virtual machines.

Benefits and considerations:

  • Applications and desktops on the master image are securely managed, hosted, and run on machines within your data center, providing a more cost-effective application delivery solution.
  • On logon, users can be randomly assigned to a machine within a delivery group that is configured to host the same application. You can also statically assign a single machine to deliver an application to a single user each time that user logs on. Statically assigned machines allow users to install and manage their own applications on the virtual machine.
  • Running multiple sessions is not supported on single-session OS machines. Therefore, each user consumes a single machine within a delivery group when they log on, and users must be online to access their applications.
  • This method can increase the amount of server resources for processing applications and increase the amount of storage for users’ data.

User experience:

  • The same seamless application experience as hosting shared applications on multi-session OS machines.

Process, host, and deliver applications:

  • The same as multi-session OS machines except they are virtual single-session OS machines.

Session management and assignment:

  • Single-session OS machines run a single desktop session from a single machine. When accessing applications only, a single user can use multiple applications (and is not limited to a single application) because the operating system sees each application as a new session.
  • Within a delivery group, when users log on they can access either a statically assigned machine (each time the user logs on to the same machine), or a randomly assigned machine that is selected based on session availability.

VDI desktops

Use single-session OS machines to deliver Citrix Virtual Apps and Desktops VDI desktops.

VDI desktops are hosted on virtual machines and provide each user with a desktop operating system.

VDI desktops require more resources than published desktops, but do not require that applications installed on them support server-based operating systems. Also, depending on the type of VDI desktop you choose, these desktops can be assigned to individual users. This allows users a high level of personalization.

When you create a machine catalog for VDI desktops, you create one of these types of desktops:

  • Random non-persistent desktop, also known as pooled VDI desktop: Each time a user logs on to one of these desktops, that user connects to a desktop selected from a pool of desktops. That pool is based on a single master image. All changes to the desktop are lost when the machine restarts.
  • Static non-persistent desktop: During the first logon, a user is assigned a desktop from a pool of desktops. (Each machine in the pool is based on a single master image.) After the first use, each time a user logs on to use a desktop, that user connects to the same desktop that was assigned on first use. All changes to the desktop are lost when the machine restarts.
  • Static persistent desktop: Unlike other types of VDI desktops, users can fully personalize these desktops. During the first logon, a user is assigned a desktop from a pool of desktops. Subsequent logons from that user connect to the same desktop that was assigned on first use. Changes to the desktop are retained when the machine restarts.

Remote PC Access

Remote PC Access is a feature of Citrix Virtual Apps and Desktops that enables organizations to easily allow their employees to access corporate resources remotely in a secure manner. The Citrix platform makes this secure access possible by giving users access to their physical office PCs. If users can access their office PCs, they can access all the applications, data, and resources they need to do their work. Remote PC Access eliminates the need to introduce and provide other tools to accommodate teleworking. For example, virtual desktops or applications and their associated infrastructure.

Remote PC Access uses the same Citrix Virtual Apps and Desktops components that deliver virtual desktops and applications. As a result, the requirements and process of deploying and configuring Remote PC Access are the same as those required for deploying Citrix Virtual Apps and Desktops for the delivery of virtual resources. This uniformity provides a consistent and unified administrative experience. Users receive the best user experience by using Citrix HDX to deliver their office PC session.

For more information, Remote PC Access.

Delivery methods