watch will just be an extension of iPhone I think it could last a lot longer than people think. It will be a notification device with many features that will still be useful 3-4 years from now. I will probably upgrade to the newest watch and also keep my first gen. No sense in having multiple iPhones unless one is for work maybe but everyone who wears watches usually has a few. I wouldn't mind having 2 or 3 generations of
watch and them all having some usability in some way. Of course, the latest generation will be the most praised and powerful but I really like the idea of the first gen watch more than any other first gen apple product in the past decade. Having said all of this, I have yet to use the watch and will have a much better idea after a month or two of use. Hopefully all of my opinions will remain the same after this trail period.I'll upgrade when they make compelling additions and finances allow. For my phone, that puts me on the S cycle.
iPhone 3 -> 3GS largely because it brought me Siri
iPhone 3GS -> 4S largely for the fingerprint reader
iPhone 4S -> 5S for background location services (if I remember correctly. Or do I have the 4S and 5S the wrong way around?)
Now I'm in the habit of updating every two years, so I'll probably continue. The only thing in the 6 and 6+ that I want is the barometer. I'm looking forward to seeing what the 6S or 7 will bring.
In short, I'm a sucker for new tech, so I wouldn't be surprised if I end up updating my watch every 2 years and I reckon the battery will be at the end of its life after 3 years, so I might as well update it then if I haven't before then.
3: 3G
3GS: speed
4: retina
4S: Siri and speed
5: bigger screen and new design
5S: finger print and M7
6: bigger screen
6S: ?