Definition of an Audiophile: An audiophile is someone who cares about or is passionate about the reproduction of high-end sound.
Well, that's the basis of it and if you want to read more of the boring yarn about the technical definition head on over to the dedicated Wikipedia page about it.
A lot of people look down their nose at so-called "portable audiophiles". They say you can't be an audiophile if you are not using speakers. They also talk more shit on forums and will bore you to death in a one on one conversation.
There is no doubt of course that using headphones or earphones will create a bottleneck in the pursuit of sound. Even my rather humble Magnepan 7 electrostatic speakers outperform over 99.9% of headphones. It's just a completely different experience.
There is no doubt that more and more people have been caring about sound quality just look at how big website such as head-fi and Superbestaudiofriends have gotten over the past few years. Not everyone has the financial resource's or space to pursue the home Hi-Fi option. Even though I have blown away every time I visit a trade show by some to the setups on offer I have never felt the need to pursue the HiFi world beyond a pair of Mangepan and Dali speakers. My lifestyle doesn't fit with it and I am sure many other peoples doesn't either.
More people are consuming audio on the go than at any other point in history. They aren't satisfied with the performance of generic bundled headsets and that's where we come in. Many people have asked why we are called Audiophile On in the past if we don't cover a lot of Hi-fi systems. My interest has always been in getting the best sounding setup possible whilst on the go. In that sense Audiophile On is an amalgamation of "Audiophile On the go" and "On head audiophile".
Whilst we accept the limitations of portable solutions that doesn't mean you shouldn't consider yourself an audiophile. You care about sound quality and you strive to achieve the best sound possible for your particular and unique situation. The hobby itself is highly subjective. For me I decided to settle on my personal amp/dac/headphone and Hifi Systems some years back but I still love testing out and reviewing new gear. I love seeing manufacturers push the limits of what, just a couple of years ago, was deemed impossible.