There is literally no way they could say "at least" with any number that would mean anything to anyone. Even if they did a range between worst case scenario (app refreshing as often as possible and running the CPU and Bluetooth radios 100%) to best case scenario (watch face that updates once per hour), would you really want to see a number that says "Between 5 minutes and 7 days of battery life!"?
You can't really even have a "under normal use" battery life claim. My Pebble lasts between 4-5 days depending on app usage. Other have theirs lasting 2-3 days. My personal iPhone sometimes needs to be recharged in the middle of the day. My work iPhone gets charged once every three days.
"Up to 7 days" is the most meaningful number they could put there, because it shows you what to expect while using it as a watch. Everything else is up to you.
> Being able to sleep with your watch on most nights of the week is a bigger deal than a lot of people realize.
This is huge for me and why I wear my FitBit instead of my Moto 360 most of the time. If I can wear it while I sleep I can set multiple alarms to wake me up that do not wake up the spouse or kids and it's less annoying than trying to turn a very loud beeping off.
There's still the drag of having to remember to recharge it every night, even if you're taking it off.
I experience this now that I've gone from the XBox 360 to the PS4. The XBox 360 battery lasted what seemed like forever. I would go a week or two without even thinking of plugging it in to charge. The PS4 controller battery life is so bad you have to plug it back in every time you're done playing.
I've had many people say "what's the big deal, just plug it in, are you lazy or what", but it is noticeably irritating.
