First, I want a single gadget that behaves as both a “smart watch” (Pebble, Samsung, Apple) and a “fitness tracker” (Fitbit, Jawbone, etc). Only the most die-hard dork would wear two of these devices.
Watches are fashion accessories, they are by definition about form over function. Anyone over the age of 22 will find themselves at functions requiring various forms of attire and a giant watch-looking thing will not be appropriate for all.
I should not have to choose between a fashion accessory and a fitness tracker and I should not look like a doofus for wearing both.
My data should be easily accessible on the web, in an app and via an API.
I expect real time sync to my phone and to the cloud, and I expect to be able to access and backup my own data through an API which does not involve a biz dev deal.
Anyone over the age of about 30 has seen many of their friends adopt fitbit. I want to participate with them rather than rant to them about how much better my device accelerometer might be.
All but the most obnoxious fitness hipster will care more about the social network than the accuracy of the device sensors.
Nobody wants to plug the damn thing in every day. It should go at least a couple of days without a charge.