I don't know what Apple was thinking when they released the iPhone with a recessed headphone jack that prevents customers from using almost any set of earphones or earbuds that they already own.

Surely someone mentioned this little fact in the beta testing? Focus groups? Oh yeah, I forgot, Apple does neither of those because they are deathly afraid of leaks.

Apple has been suspiciously quiet about the topic and I haven't heard a single rational explanation as to why Apple would do this. To protect the port from damage? For acoustical reasons? Without a sound logical explanation, we're left to wonder. Is it so that buyers will be forced to use Apple's iconic white headphones so that they can further promote the brand? I hope not. Is Apple creating an "opportunity for third parties." I doubt it, they're not that charitable.

I think that Apple's white earbuds sound lousy and I always replace them. The last several iPods I've purchased still have the lame-o white buds still in their original packaging.

When iPhone was released on 29 June there was exactlythird-party headphone/microphone available at launch (and from the Apple online store ), the Vibe Duo from(US$101, pictured). Since the Vibe Duo was available in Apple stores at launch, they obviously had advanced notice about the iPhone's recessed jack (word is that they only had six weeks). I'm glad that someone did! I'd love to see the NDA that they had to sign.

The Vibe Duos sound great. I put sound quality at just a hair below my current favorite iPod earphones–the Atrio (US$199) from Future Sonics. But they are darned close and I was listening really closely in a quiet room with my custom molded SofterWear sleeves (US$149) on the Future Sonics.

The advantage, of course, is that the Vibe Duo contains a microphone so that you can make and receive phone calls while listening to the iPhone in iPod mode. These may finally kill my need for a dedicated iPod shuffle for the gym. Sure, the iPhone is much larger, but having access to the Web and email kills my need to bring reading material for those long cardio sessions. Could the iPhone spell the death of magazines and newspapers?

The only down-side is that the microphone on the Vibe Duo doesn't have a built-in actuator (like the Apple set) that allows you to click to mic to advance to the next song. Boo hoo. While that would be nice, it's not a deal breaker for me.

There are options like the Belkin Headphone Adapter for iPhone (US$10.95) which allow you to use any standard headphones with a 3.5mm plug with iPhone, but they don't have the aforementioned microphone option. So while iPhone headphone adapters are great for plugging your iPhone into your car's cassette adapter, they're not quite as useful for full-time headphone use.

What headphones do you use with your iPhone?