I've only been waiting since Nov. 30.
It arrived nicely packaged, but had zero charge - although it appears that it had a little charge during shipping, as it recorded steps on its journey.
The form factor is surprisingly small. It's narrower than even the Fitbit Flex, but not quite as flat. The main body is not as long as my wrist is wide, which is good...I had to return the Surge because it was longer than my wrist width and was actually painful to wear. The Up3 has a thickness of maybe half an inch at its thickest point.
The wrist band has a catch which appears very secure, and is adjustable. I have a small wrist, but it appears that I could wear the same band if I gained another 1.5-2 inches of girth in my wrist. It's quite comfortable to wear, even with it adjusted somewhat tight to ensure the sensors maintain contact. The band is very soft and flexible.
Connection was very easy once I got my band charged. You just tap and hold your finger down on the top of the band while your phone searches, and it pairs easily. I've heard complaints from others that it can be difficult to get the band to recognize a tap, but so far I haven't had that problem. You also tap to switch the band from sleep to active and vice versa. Apparently, per Jawbone, you need to put the band in sleep mode so that it can track how long it actually takes you to fall asleep once you've settled down to do so. This apparently is affected by things like when and what you ate, what kind of activity you engaged in before bed, etc., so that's why they say it doesn't detect sleep automatically.
The app is nicely laid out, very intuitive, with a good bit of information. I would love a desktop version with more indepth info, but alas, that's not available.
The band has options for inactivity alerts which you can set for various times, a vibrating alarm clock, and reminders. I haven't tested yet to see how strong the alarm vibration is.
There's heart rate sensors, but right now it only tracks resting heart rate. I won't see that until morning. Supposedly there will be a future update which will expand heart rate tracking capabilities. That matters less to me than it does to some people because I had the Bodymedia Fit, which was extremely accurate on calorie burns without ostensibly tracking heart rate...it had the same bioimpedence sensors and tracked all kinds of things which it used to calculate calorie burns, but it did not present the data for those sensors where you could see them. I expect the Up3 to function in a similar manner.
Tomorrow I'll be able to update with more information on accuracy/resting heart rate/etc.
