- Sleep tracking. Very useful, if a bit shallow. Revealed issues to me that I'm working on now.
- Exercise tracking. The manual stuff is fine, but the automatic tracking is bad. Sometimes it thinks a car ride is a bike ride. Doesn't pick up long walks half the time. My friend uses the built in stuff on his Android phone and it seems to work better.
- Heart rate monitor. All it gives you is a crappy line graph. Doesn't seem very accurate. This feature is too shallow to be useful.
- Moving reminders. All you can do it set hours and days for a 10 minute reminder before the end of an hour. I don't even notice the reminder most of the time. Its inflexibility makes it pretty useless for me. More robust reminders and a calendar integration would probably help.
- Weight tracking. Not really helpful to me, as I weigh myself each morning on a regular scale.
- Water intake. Never used it.
- Calorie tracking. The UI isn't very helpful if you cook your own food. The calorie tracking display is often wrong and contradictory. I filed a detailed bug report and linked a bunch of online forum posts with the same problem, to get a canned response about reinstalling the app.
- Step tracker. I drum on my desk alot and it mistakes it for steps. This makes it really inaccurate for me.
I'll probably keep using it till it dies and look at other options like Oura.
The sleep tracking function was OK, but I think it is not robust enough to be worn 24x7 (less the 5-6 hours it takes to recharge). From various tests, the step counter seems to be in error more than the claimed 5%. I still use the phone app to track my weight using a conventional (non-Fitbit) digital scale and entering the values manually most days.
It's one of those techy things. When you don't have one you think of all the benefits. After months of ownership the novelty wears off and it is all rather mheh. Fitbit keep sending me emails to upgrade to their latest and greatest. Seriously, you can buy a Seiko Kinetic watch for the price of a low end Fitbit and the Seiko will work for decades without even needing a new battery. Why keep buying ever more expensive smartwatches?
You have to charge most smartwatches fairly often, and most people charge them at night, so sleep tracking is difficult. Plus I've read that some of them don't do sleep tracking very well, and I can confirm that with my experience with the Apple Watch 4. It would indicate I was asleep when I knew I was awake (like to use the restroom in the middle of the night), and would indicate I was awake when I'm pretty sure I was asleep.
I bought a cheap-o Mi Band or whatever it's called, and was using that for sleep tracking. It was like $25. I would suggest you start with that. Their Mi Smart Band 4 advertises that it tracks sleep, so maybe it does a good-enough job?
The closest I came to it was something from Garmin, rather small but with a display. I stopped using it as it became apparent that their data privacy policy was awful, I either could consent to everything or their app would basically be useless. This is over 1 ago, they might have changed the policies, don't know.
I have surrendered to the market now and got an Apple watch. It at least ensures that the data is not spread to additional companies, as apple has the data anyway. It's a nice product, but honestly mostly a gimmick for me.
It works nicely as a watch too, though unless you pay top whack they aren't very fashionable looking.
I don't care much about apps, but I do care if it can connect to other equipment (like a rowing machine or a turbo) so being ANT+ compatible is important to me.
Bonus: You can charge the whoop while you wear it so you don't miss out on sleep tracking as is mentioned in other comments.
For me it's got the best balance between features and simplicity.
Any more features and the battery (life or size) would be worse.
Sleep and step tracking is average, notifications are just right.
I'm hoping a reasonable replacement surfaces before it dies, and am still sad Fitbit destroyed this product, and won't be considering any of their products for that reason.
In the future I would probably get more high end Garming so I can have my cycling route on the watch to follow it.
I initially went for it for stuff like notifications and hoping it would make me more productive and help me track my time better. Ultimately, I think the ecosystem has potential but it's in its infancy currently.
Main good points, though:
- Fitness tracking. If you do things like running or swimming you'll benefit from the watches. Most useful functionality is for fitness.
- Elderly people. I think the functionality for falls, although it seemed like a joke to some, can actually be pretty useful for older people and encourage more independence.
I think it has the potential to be useful in more areas:
- Health. I think the heart rate and ECG is genuinely beneficial. Many people have cardiovascular conditions or are on medication and doctors advise them to take regular checks of heart rate, blood pressure, etc. But in my experience with the Series 3, the heart rate functionality was a mess. My HR was around 65, whenever I opened the app on my watch it would start at 120bpm and slowly go down to my actual HR. It would log all the results in the watch app, even the very incorrect readings of 120bpm. I hope they fixed this since.
- Sleep tracking. The Apple Watch doesn't currently have native sleep tracking, though 3rd party apps exist that I've never tried (they may be hit or miss). I'm not sure how accurately a watch can track sleep data anyway. Rumours suggest the Series 6 may have sleep tracking. I think this would be useful - my sleep sucks often and I'd like to have more data on it.
- Notifications. One of the main reasons I got it, but it's not very useful. It doesn't save any time compared to just looking at it on your phone, and you often can't do much about a notification on the watch.
- Reminders. Medication, water, movement. I never used this functionality on the watch, if it has it, but for people in desk jobs, taking medication, etc., I think they're pretty useful.
- Authentication and identity. It already has Apple Pay, and it can unlock your Mac, but I'd like to see it go further. I think it'd be a good way to conveniently replace a wallet.
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Right now, I would only get a watch if you're into fitness, to be honest. I think they have promise, but aren't there yet. Perhaps stuff has changed since the Series 3, but from the updates I've seen I think it's still not there yet.