What’s the best iPhone app, or even the top 10? Those questions are impossible to answer.

Even if you think you have the best one, the odds are something new will come out to bump it down the list within a day or so.

A great help to sort through this iPhone app phenomena is a new book and Web site from O’Reilly Media.

Best iPhone Apps: The Site for Discriminating Downloads sums up the programs for 200 eye-catching and useful solutions. Author Josh Clark stress-tested thousands of apps with a goal of identifying those that make the most difference in a user’s life.

He considered home, work, play and travel when making his decision. Each app was chosen to help users be productive and organized, play games and travel along while getting in shape.

I in a recent email exchange, I asked Clark what his favorite app was. Choosing one is tougher than it sounds, he said.

“With over 65,000 apps to choose from, it was sweet torture boiling the book down to its 200-plus recommendations, and picking a single favorite app to sit at the top of the pile feels almost impossible,” he said.

His choice was Instapaper (free or $4.99 premium version). “Instapaper.com is a simple, free service to store Web pages for future reading,” Clark said.

“Instapaper’s iPhone app fetches those articles from your online account and holds them until you’ve got the time and attention. Even better, it strips out all the graphics, ads, and gobbledygook on the web page, giving you plain text without the distractions,” he added.

Clark even gave me his top 10 apps, so here is the rest of the list:
•    Stanza
•    Twitterrific
•    Yelp
•    Quickoffice Mobile Office Suite
•    Now Playing
•    ATM Hunter
•    RunKeeper
•    Epicurious Recipes
•    Shopping List
•    Rolando or Rolando 2

A complementary site (http://iphoneapps.oreilly.com) lists new apps. Users also will find a Best App Archive, which is broken down into many different sections, including a section called Tips & Tricks and also App Smackdown where users can vote for selected choices in a competition.

http://oreilly.com, $19.99

If you are looking for compact, lightweight headphones that you don’t have to stick into your ears look no further then the Phiaton PS 320 headphones.

What I look for in a set of headphones is good crisp sound along and the ability to forget that they are on my head and in use. This is the case with the PS 320s.

I found them to be comfortable with nice, consistent sound; they also fold into a nice small compact case for traveling.

Once unpacked, the unit has two small padded ear pads that rest on your ears in comfort. From there just plug in the attached cable to any media player, and you are ready to rock.

While they are not considered to be a noise-canceling product, I did wear them on a recent flight, and outside noise was never a distraction.

www.phiaton.com, $199

Verbatim has announced some storage products with its launch of the SureFire line of portable 2.5-inch hard drives available in a FireWire800/USB 2.0 combo.

The palm-sized products are available with capacities of 250GB, 320GB and 500GB. They have a 5400rpm spindle speed along with 8MB of cache memory to optimize performance.

Both Mac and Windows users can plug the drives in to any laptop or desktop unit with the available ports without an AC power adapter.

The hard drives have one USB 2.0 port and one FireWire® 800 port, which will give users transfer rates of up to 800MB/sec. for FireWire 800 connections. Users of the USB 2.0 connection will get speeds up to 480MB a second.

Along with the functionality, users will like the look — they are housed in a stylish, durable black aluminum-extruded case that has a fingerprint-resistant, matte finish.

A black protective carrying case is also included along with FireWire and USB cables.

www.verbatim.com, $109.99 for the 250GB version, $139.99 for the 320GB and $179 for the 500GB.

– Gregg Ellman