Just which apps should you put on your newly acquired mobile device? After all, with 100,000 or so mobile applications clamoring for your attention in the App Store, that pretty much rules out the process of trial-and-error.

I think I can be some assistance in helping new iPhone and iPod touch owners get their start with merrily downloading mobile apps. Since the App Store first opened its doors about a year-and-a-half ago, has published its share of iPhone app reviews, and I've edited nearly all of them. If I haven't used an app personally, I've talked to someone who has, which puts me in a pretty good position for making recommendations on which programs should be filling up your mobile device.

So where to start? You'd be well advised to peruse , which recognizes our 20 favorite apps of 2009. Opinions may vary, of course----but our list is a pretty good starting point.

That said, loading up an iPhone or an iPod touch is a pretty personalized task that depends heavily on your likes and goals. For example, as great a reference tool as may be--and we think it's one of the best ones out there--if you're not all that in to bird-watching, that's an app that won't serve you particularly well. (If you into bird-watching, head directly to the App Store and download this comprehensive reference guide immediately.)

The first thing to consider when looking for apps to put on your newly obtained iPhone or iPod touch, then, is just what do you plan on using your device for? Is it a business tool? A communications device? Just a way to keep yourself amused and diverted when you're standing in line or stuck on an interminable commute? Or some combination of all those things? Once you've settled on that, it's easy to track down apps that will serve your purpose.