[victorvation]

"Wake to Sleep" seems to be the generally accepted definition, i.e. you won't have to charge it during the day during normal usage. How long you're awake for can vary though, I've seen anything from 8 hours to 20 hours of battery life be referred to as "all day".

[TeMPOraL]

Accepted by whom?

I hate it when marketers get to make up their own meaning of commonly used words, usually making them mean less than they ordinarily do. With "all-day" meaning anything between 6.5 (see parallel comment) and 20 hours, it's becoming a worthless and purposefully confusing term.

(Note if that a physical store advertises it's open "all day", you expect it to be open from 00:00 to 23:59.)

[ogre_codes]

Well in this case you don't have to wonder what it means because they say exactly how long—18-hours.

Also, nobody says "open all day" in retail because retailers would be more explicit about the fact that they are open at night, thus you have 24 hour convenience stores, not "all day".

[mc32]

It’s no better or worse than the old “lifetime” warranty which varies from guarantor to guarantor. Oh, it means “service life,” oh it means “while original owner uses it”, etc. They are all bad. They should say what they mean and not hide behind their own definitions (which can change over time).

[victorvation]

"Accepted" by marketers, which I guess is your point. The term is meaningless

[ocdtrekkie]

Clearly this means they don't intend Apple Watch to pick up sleep tracking though. My Fitbit needs to last a few days because there's only a couple chances I really take it off to charge.

[jedberg]

Sleep tracking is a headline feature of OS6. Clearly the marketing department... didn't talk to the other part of the marketing department.

[saagarjha]

I wouldn't call it a headline feature, since it's not on this page: https://www.apple.com/watchos/watchos-6/. Honestly, did they mention it at all?

[jedberg]

I think it didn’t make the cut at the last minute. The code has been in the betas for a while and there have been a bunch of “rumor” articles about it. Usually when there are that many rumors they’ve been seeded by Apple PR.