It can, of course -- numerous apps make this possible. But some, like LogMeIn Ignition, sell for upwards of $30 -- not an unreasonable price, but perhaps more than you want to spend for such an app.
That's why I'm a fan of newcomer NTRconnect, which offers free remote access to your PC from your iPhone.
Just install the NTRconnect Free utility on your Windows or Mac system, then load NTRconnect Viewer [App Store link] on your iPhone (or iPod Touch). After creating an account and a few setup steps, you're all set for remote desktop-sharing goodness.
Controlling the PC is surprisingly easy: dragging your finger also drags your mouse cursor and scrolls the screen as you get near the edge. You can pinch/reverse-pinch to zoom out and in. A tap equals a mouse click, while tapping with two fingers gives you a right mouse click. There is, of course, an onscreen keyboard you can toggle for data entry.
Don't expect to get any actual work done this way, but if you need just a short burst of activity on your computer -- retrieving a file, running an app, etc. -- it's fine.
And you can't beat the price. For what it's worth, there's a $1.99 NTRconnect Remote version of the app that adds more features, like security reports, file transfers, and support for more than two computers. (Plus, NTR makes a donation to TreeLink, a nice "green" perk.)
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