Anyone who has ever found themselves lost in a Ripley’s Believe-It-or-Not book, or the Guinness Book of World Records, will understand the appeal of this simple but entertaining app. In essence, 5,001 Amazing Facts puts a fat stack of electronic filing cards in your hands, each one displaying a single fact – admittedly, some more “amazing” than others – about this weird and wonderful world we live in.

Equip your Nokia mobile phone with this software and you might distract yourself while waiting for the dentist, or keep yourself entertained while riding the bus. Glean a striking factoid or two – that the numbers 1 through 36 on a roulette wheel add up to 666, say, or that the most popular waist size in men’s pants in the U.S. has grown from 32 in 1985 to 36 in 2003 – and be the life of the next party. Impress friends, family, and colleagues when you tell them that catfish are the only animals with an odd number of whiskers, or that there’s a French novel whose 233 pages contain not a single verb.

Particularly impressive is the app’s clean, gesture-based user-interface. Each fact is presented as its own full-screen page, in easy-to-read type. To summon up the next fact, or to return to the previous one, you just slide your finger across the screen to the left or right. As you do so, the current page slips offscreen and the next one slips into its place, accompanied by a brief shuffling sound.

In addition, facts may be searched by keyword and you can mark particularly interesting ones as favorites for easy retrieval in the future. The app also bookmarks the last fact you’ve looked at so that you can pick up from where you left off in a prevous session. Another highlight: The app makes it push-button easy to send selected facts to your pals via SMS text messaging (it hands the message off to your phone’s default SMS client).

Things we’d like to see: For one, dates, where appropriate, and attributions. Think how cool it would be if each fact came with a hyperlink leading to a Web page full of additional information about that topic. Also nifty would be add-on packs, perhaps devoted to specific categories such as sports, entertainment, science, and history.

Some better, ahem, fact-checking would seem to be in order, too: For instance, all the gold ever mined is actually estimated to form a cube of just 66.5 feet on a side (is that not amazing?), not the 60 feet that this application states. Finally, quite  a few of the facts offered here – like the one about a Dallas restaurant having won a prize from Esquire magazine – fall somewhat short of jaw-dropping.

But these are quibbles. The 5,001 Amazing Facts app – which for some reason changes its name to World Fun Facts as soon as it’s up and running  - is good, clean fun for children of all ages. And the price – $1.99, or even free for a limited “Lite” version – can’t be beat.