Baloney. Not accurate enough for what? Professional runners, cyclists and mountaineers use standalone GPS watches now, but for you - not accurate enough, right.
GPS units have varying degrees of accuracy and some are great.
Apple's watch is a toy, and the 'sports' moniker they've donned on one model is a joke. Look at the functionality and performance of standalone sports watches and the Apple watch looks like a prop from a 1970s B movie. I was embarrassed for Apple when they said you can 'use the GPS and wifi.. from your iPhone'. 2014, and they release a tethered peripheral device for the iPhone. And that's what it is - an iPhone accessory for people who don't really need one.
People who take sport seriously will be sticking to Garmin, Suunto etc for a while yet it seems.
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What year/planet are you guys in. I can Ultra-trac for over 3 days on my GPS watch. It's the same with BT. BT LE can be running with GPS for around 12 hours on a watch now. That means you could be out doing an ultra listening to music (on your bluetooth earphones paired to watch) while having your route recorded - just on your watch. No need to carry the bulk of a phone.
That's not what Apple want. They want you tied into buying and upgrading a constant cycle of both iPhones and Apple watches. It's about conversion, not componentry.