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Application virtualization can be a good way to deliver apps to users, but it's not always the best way.
Isolating applications can lead to reduced functionality or even make your apps more prone to crashing or freezing. Of course, you don't discover that kind of issue until workers start actually using the applications -- nobody knows how to find nuanced performance issues better than a pack of users.
Some problems with app virtualization arise simply because certain apps don't like to be virtualized, but issues can also stem from problems with the packaging (or "sequencing") process. There can also be problems with the original application. The challenge you have is to figure out where the problem is coming from so you know where to go for support. (Hint: It's probably something you'll have to fix yourself.)
On top of the problems that can come with application virtualization, you'll still wind up using some applications that are locally installed on the desktop, so it's not like app virtualization gets rid of one delivery method for another; you just add a new one.
App virtualization works for some, but not all
I don't want to be all doom and gloom on application virtualization. It has many wonderful use cases. For example, some apps are a challenge to deliver in the traditional way, and they can be packaged nicely. Other apps need to be isolated from one another, either because they don't like to be on the same machine with other applications, or because you need multiple versions of the same application.
Make no mistake, application virtualization is awesome, but it's easy to get romanced by it and create more work for yourself.
Vendors are starting to figure this out, which is why VMware acquired CloudVolumes. That product has been renamed App Volumes to better convey what it does: compartmentalize entire applications for deployment. App Volumes creates individual virtual machine disk (VMDK) files for applications and attaches them to desktops or virtual machines as needed. There's little trickery going on behind the scenes with regards to isolation and sequencing -- it's straightforward application delivery.
FSLogix arrived on the scene around the same time as CloudVolumes with an approach that you could argue is even simpler than bolting on VMDKs: With FSLogix Apps, you install all the apps into one image and hide the unwanted ones from Windows. In this case, all the apps are already there, and you can push out policies that allow Windows to see them as installed.
I'm a huge fan of compartmentalizing applications for easier management and delivery. Today's world is different because we can do that logically or physically. The choice is no longer limited to "streamed or local." Application virtualization has its use cases, but it is not the end-all method for application delivery. It should only be used when appropriate so that you don't end up making more work for yourself trying to virtualize an application that would be better off run locally or via one of the other products on the market today. The next time you're faced with an application delivery challenge, ask yourself if application virtualization is appropriate. If not, look into some other options before falling back to local apps.
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