SAN FRANCISCO (Reuters) - Touchscreen phone users are discovering that much of the fun in their devices stems from applications -- those little nuggets of convenience, amusement and distraction available for download on the slightest whim.

A good example is Google Inc's newly updated Mobile App for Apple Inc's iPhone, which has been generating a lot of buzz for one main reason: voice search.

Want to find the nearest pizza place, showtimes for the James Bond movie "Quantum of Solace," or the latest Bruce Springsteen video? Google voice search is uncannily accurate.

But it has obvious limitations, particularly with names. Say "Barack Obama" and you get a full page of data. Try "Emile Zatopek," the famed Czech distance runner? Forget about it.

Of course, there are many applications available for download on all sorts of mobile phones, but touchscreen devices have emerged as consumer favorites.

While the mobile app race is still in its infancy, the iPhone is already well ahead of rivals such as Research in Motion Ltd's BlackBerry and T-Mobile's G1, which features Google's Android operating system.

But competition is going to get more intense. RIM's touch-screen Storm was launched last week, although its app store won't open until next year. The Android app store opened for business last month but so far hasn't generated nearly the momentum of the iPhone app store, which went live in July.

In the first two months, iPhone users downloaded 100 million apps, choosing from among thousands of options. The programs, the vast majority offered by third-party developers under the watchful eye of Apple, run the gamut from utterly frivolous time-wasters to the surprisingly useful.

In addition, many handy iPhone apps are available for free, not a small consideration in these troubled economic times.

FOR FOODIES, ECO-CONSCIOUS, MUSIC LOVERS

The free Shazam mobile app is now available on the Android platform, following its successful debut on the iPhone. The program has developed a devoted following among music lovers as it seeks to solve the age-old question: "What is the name of that song?"

If you hear a song playing -- on the radio, or blasting from a car stereo -- and want to know more, launch Shazam and the program will capture the song, check it against its database and display the song information.

Another popular free app for the iPhone is offered by UrbanSpoon, which features user-generated restaurant reviews, but with a twist. If you feel like trying something new, just punch in your criteria, shake your iPhone, and UrbanSpoon will pick a restaurant for you.

The clever interface looks like a slot machine, and is a good way to break out of a food rut.

Ever been at the supermarket and found yourself wondering how safe or green a certain product might be? The free GoodGuide app -- still an iPhone-only offering -- features ratings on more than 60,000 household and personal use products.

Just punch in the product name and GoodGuide gives you a ranking based on environmental safety, impact and labor policy.

Consumers can expect to see many more mobile apps in the coming months, as the sheer creativity of small, third-party software developers should keep the market buzzing for some time.