This feat was made possible by a new iPad app I've been testing called Parallels Access, released Tuesday, which can remotely control either a Mac or a Windows PC. It isn't the only iPad app that can remotely control computers, but of the ones I've tested, it does the best job of treating the computer programs it accesses as if they were iPad apps, without sacrificing functionality. The programs continue to reside on the computer.

Parallels, a company based in Seattle that's best known for its namesake program that allows Macs to run Windows, calls this 'appifying' your computer programs. What it means by this is that it adapts them to the iPad's familiar interface, including app launching, touch gestures, scrolling and text selection.

Unlike many others, it doesn't force you to constantly try and emulate the precise mouse pointer for which most of these computer programs were designed. It runs them like iPad apps, in full screen, and at the iPad's resolution, yet preserving full functionality and the ability to switch among open apps and windows on the computer. It works over both Wi-Fi and cellular connections.

Despite some drawbacks, Parallels Access is a very good way to make your iPad more of a productivity tool and to integrate it with your computer, without forcing you to use your iPad the same way you would use a computer.

The two biggest drawbacks involve price and file transfers. Access costs a hefty $80 per computer per year, though there's a two-week free trial for every Mac you use. For Windows machines, it's free for 90 days because compatibility with Windows is still in the beta phase (though it worked quite well in my tests).

Also, the app cannot yet directly move files from computers to your iPad, though the company is working on it. For now, to get a file from the computer to the iPad, you have to remotely call up the computer's email program and send it to yourself on the iPad, or upload it via a file-sharing service like Dropbox on the computer, and then retrieve it from the Dropbox or similar app on the iPad.

Another limitation: It doesn't work on Android. The company says it is considering an Android tablet version of Access, but has no immediate plans to release one.

Here's how it works. First, you download the free app to your iPad, then you install a small companion utility on your Mac or PC, which runs in the background. Then you fire up the Access iPad app and you see a home screen with all of the available computers. Just click on one and the iPad takes it over. The link is established over a secure, encrypted connection, and you can opt to lock the computer and blank out its screen during the remote-control session. You can also opt to require the use of the computer's login credentials.

Once you have the computer on your iPad screen, you don't see its normal desktop, with tiny icons generally meant for a mouse pointer. Instead, you see a Launcher screen in which your Mac or PC apps are presented like large, iPad app icons. You can add or remove app icons.

You tap an icon and the program -- like iPhoto or Microsoft Excel -- appears in full-screen view on the iPad. I tested a wide variety of Mac and PC apps and all worked fine via Access, with almost no lag, even over a 4G cellular connection.

Access places a small toolbar at the edge of the screen, which can be moved or hidden. This can take you back to the Launcher, bring up a bar at the bottom that lets you switch among apps and windows, and brings up the iPad keyboard, which is augmented with special keys the iPad lacks, but computers use. These include Escape, Tab, function keys, Control, Alt, arrow keys and the Window key on PCs or the Command key on Macs.

The toolbar can bring up settings, which allow you to go into mouse mode, just like a PC; reveal the whole desktop; and display the special keys without the whole keyboard.

I was able hear the sound on the iPad from audio and video files, and select various menu items and icons. Access invisibly modifies things like small toolbar icons so that, even if you tap on them imprecisely, they still activate. I even dictated text using the iPad into a program on the remote Windows PC.

Parallels Access really shines when typing. I was able to type easily on the remote programs.

When you select text, it brings up the standard iPad selection handles and the standard black iPad control bar for things like copying and pasting, just as if you were in a standard iPad app. For more precise selection, it brings up the standard iPad magnifying glass feature, and if held down a bit longer, it even places a mouse pointer inside the magnifier. I used this to resize a photo in a Word document. (This particular task takes some practice.)

The program includes many touch gestures and taps. A two-finger tap acts like clicking the right button on a mouse and other simple gestures allow things like dragging and dropping.

For Windows 8, Parallels Access places both traditional programs and the Start-screen touch apps together in the Launcher, so you don't have to switch modes. In my tests, it worked well with both kinds of programs. On the Mac, if you are using Parallels Desktop to run Windows programs side by side with Mac programs, both types of programs show up on the Launcher and can be used remotely.

I ran into zero glitches when controlling a Mac remotely. And even though the Windows access is in beta, I ran into only two glitches: a single instance of jittery scrolling in a photo program on the remote PC, and a single instance of lack of audio from the iPad when playing one of many videos I tested remotely.

If you're willing to pay the money, Parallels Access is an excellent way to make remotely controlling a Mac or PC from an iPad a frustration-free experience.