Microsoft this week released the first-ever public release of its long-awaited Remote Desktop app for Windows Phone. But it comes with some caveats: It's a prerelease version of the app that doesn't include some key functionality. And it will only work on Windows Phone 8.1.

Microsoft Remote Desktop Preview is available now from the Windows Phone App Store.

Intriguingly, the app list notes that it is "Made for Windows Phones and Windows PCs," which is the language Microsoft plans to use for universal apps—i.e. those apps that can run on both Windows 8.1 and Windows Phone 8.1—though it's unclear if this is really a universal app. If it is, it's not as full-featured as the Remote Desktop "Modern" app that ships with Windows 8.1 today. (It doesn't support Remote Desktop Gateway, yet, for example.) Perhaps it's a newer version of the app, however.

Update: Turns out this doesn't indicate that the app is universal. Instead, it takes advantage of the cross-platform licensing that is now possible between Windows 8.1 and Windows Phone 8.1. Which is a weird thing to note, since the app is free. --Paul

The app is simple enough to use. Just configure the server(s) and PC(s) you wish to connect to remotely, along with optionally pre-supplying your sign-in credentials. Then, just tap the appropriate tile to connect to that PC.

One thing you'll need to deal with—as you would with PC-based remote connectivity—is getting your phone past whatever gateway sits between it (out in the world) and the PC/server (on its internal network); Very few PCs and servers are directly connected to the Internet with a public IP address. On the PC, this is simple enough: You can use consumer-capable VPN solutions like Logmein Hamachi for example. On a phone, however, this isn't possible. Windows Phone 8.1 ships with integrated enterprise VPN capabilities, so I assume you would use that. But it would need to be supported by your workplace.

Here at home, I just tested this app on my local network. I have a few servers I can connect to and some PCs. I found that my first tests always failed—it just wouldn't connect—but that when I disconnected the cellular data connection and just used Wi-Fi, it connected fine.

The experience varies by device. If you've got a Lumia 1520, which has a roomy 6-inch screen with 1080p resolution, it's not much different from doing so from a mini-tablet. But it's a bit more painful to use on smaller phones.

The software has some nice touches. There's a Zoom button you can use for swipe-based navigation around a zoomed-in screen.

And the integrated soft keyboard works well, though you should note that the top row of keys—Windows key, CTRL, ALT and so on—are "sticky," so you can't just tap the Windows key to go back to Start. However, the CTRL + ESC keyboard shortcut works fine, as any old-timer would expect.

Remote Desktop Preview is exactly what it seems like, and if you're using a compatible VPN at work—sort of a toss-up, frankly—this could be exactly what you're looking for.