The Apple Watch Review
by Joshua Ho & Brandon Chester on July 20, 2015 8:00 AM EST- Posted in
- Wearables
- Apple
- Mobile
- Apple Watch
Battery Life
The Apple Watch, more than any other wearable, presents some enormous barriers for battery life testing. On the smartphone side, testing has traditionally been pretty simple in the sense that you can usually design an app, script, or some other form of automatic test that will run a specified workload. The display is set to not timeout by either an application that adjusts the timeout to an extremely large value or by adjusting the timeout in the settings menu.
Meanwhile for wearables, on Android Wear, testing battery life is generally quite simple, because you still have some control over the timeout settings, you can set manual brightness, and the display automatically turns on when you receive a notification. On Watch OS, exactly none of those things are true. As a result, objective battery life testing of the watch has a number of significant challenges and thus far I haven’t seen any real solution to this problem. We hope to have a standardized battery life test across all wearable OSes in the near future, but for now this section will be purely subjective in nature.
38mm Apple Watch Battery (Image Courtesy iFixit)
To really sum up battery life on the Apple Watch, it’s definitely more than sufficient. I never recall having battery life drop below 30% in a single day of use. If a day was particularly slow in terms of notifications, I often would end the day with more than 50% battery life, so going two days wasn’t completely impossible. However, in practice I found myself charging the watch every night.
Just by virtue of the glance-based nature of the watch, battery life continues to be far better than the iPhone 6 over the course of the day. I did notice that idle battery life isn’t particularly strong on Apple Watch when wearing it on my wrist, presumably because things like the haptic feedback, fitness tracking, and background sync activities have to be running quite often. Something like reading email doesn’t seem to drain the battery all that quickly, which is also helped by the consistently low average picture level (APL) throughout the UI. However, I would notice throughout the day that the battery percentage seemed to decrease even though I’d go the whole day just checking the time. Given that the workout mode also seems to have a pretty significant workload, I suspect fitness tracking is a significant component of this idle drain.
For a first-generation product on 28nm, this level of battery life is actually rather remarkable as I expected wearables to go through a few generations of somewhat poor battery life before reaching an acceptable point. Although performance isn’t amazingly fluid on WatchOS, it’s definitely more than made up for due to the improved battery life that comes from such a low-power SoC. Roughly speaking, Apple has definitely met their promise of 18 hours of battery life, and arguably exceeded it. Of course, given that there’s no real data here yet opinions may vary widely on whether the battery life of Apple Watch is acceptable.
Charge Time
Although battery life is usually the primary way in which people determine how good a device is at staying mobile, charge time often enters the equation. I’m sure a lot of people have experienced situations in which charge time becomes critical. Traveling will often affect this, as power outlets are fairly rare in airplanes and airports, which means that the time spent at a power outlet needs to be as productive as possible in terms of increasing battery charge. In the case of the Apple Watch, the only option for the average user to charge the watch is with a wireless charger that uses magnets to hold the charger in the correct position on the watch. This wireless charger is fed by Apple’s standard 5V, 1A charger. In order to test this, we monitor the time it takes for the wearable to go from a completely drained state to a fully charged state.
It’s probably no surprise that our test results track relatively closely with listed Apple spec at 2.68 hours. What isn’t listed in the spec is that like every other wireless charger I’ve tested thus far, trickle charging with wireless charging isn’t really trickle charging to the AC adapter. I thought something might have just been off with the Moto 360, but after my experiences with the Apple Watch it’s clear to me that wireless charging behaves differently from wired charging. As a result, it wasn’t unusual for me to wake up 9 hours after putting the watch on the charger and still feel that the watch was quite warm from charging. At any rate, given the need for wireless charging on wearables I suspect that we’re already at the limits for charge rate on wearables for the near future given the increased heat output of wireless charging.
Taptic Engine
As I’ve mentioned earlier in the review, one of the biggest points of differentiation with the Apple Watch is the use of a brand new haptic feedback system that Apple calls the Taptic Engine. At a low level, this is just a linear actuator, but the system is very different from a traditional linear actuator.
For those that are unfamiliar with traditional linear actuator haptic feedback systems used in smartphones, a voice coil has voltage applied across it, which allows current to flow and generates a magnetic field because the voice coil is an electromagnet. This voice coil acts on a mass, which vibrates in a small cell at a certain frequency. However, in the traditional y-axis configuration of most linearly-actuated feedback systems, the limited length means that there isn’t a lot of room for low frequency vibrations.
Source: Precision Microdrives
In the case of the Apple Watch, it seems that Apple is using a z-axis vibration motor combined with the speaker. Relative to the PCB on the watch, the weight and the length of travel for the mass is enormous. This inherently allows for much better haptic feedback at lower frequency vibrations. This haptic feedback motor design, combined with the speaker, is what makes up the Taptic Engine.
Source: Precision Microdrives
The question now is whether Apple has actually accomplished significant here for the end user experience, and the answer to that is definitely a strong yes. When this feature was first announced, I wasn’t particularly interested in it because I’ve never really been one to pick nits over haptic feedback which is why I never point out a phone’s haptic feedback system as a key point of differentiation unless it’s egregiously poor. However, in the case of the Apple Watch it’s an enormous step up from what one might be used to from a phone because of just how distinct it is. It really feels like someone is tapping me on my wrist when notifications come through, and it’s sufficiently distinct from conventional vibrations that I’ve never failed to miss a notification that comes in, which happens every so often with my phone or even other wearables.
Apple S1 Taptic Engine (Image Courtesy iFixit)
There might be some missed potential here though, as it would be great to have more variation to the vibration patterns to indicate various types of notifications as I usually can’t reliably guess what application a notification came from by the haptic feedback alone. The system is also remarkably quiet compared to vibrations from phones, presumably because the frequency of the noise is relatively low and the watch is strapped to the wrist, which muffles noise. As said before, I normally don’t care enough about vibration feedback to write anything about it, but in the case of the Apple Watch the difference is big enough to be notable in terms of user experience.
Misc. Thoughts
As far as I can tell, the speaker is decently loud for relatively quiet environments but it’s easily drowned out by background noise. I also found that I almost never took the watch out of silent mode, as the haptic feedback is enough and audible ringtones definitely lack the relative subtlety that comes just vibrations.
On the receiving side, I was pleasantly surprised by just how effective the microphones are at rejecting noise, as it rejects anything reasonably far away and seems to amplify nearby voices based upon some casual testing of iMessage audio messages. However, Siri seems to struggle a bit with noise rejection and I’m pretty sure that Google Voice Search continues to be faster and less error-prone than Siri when it comes to dictation.
As best as I can tell, Apple Watch currently doesn’t detect sleep states or much of anything around sleep, which is definitely an area of potential improvement as it would be amazing to have an alarm clock that would go off at the end of a sleep cycle to reduce sleep inertia. Sleep tracking in general would be a significant feature if executed well, although this would likely require significant increases in battery life so that an average workload would only use around 40% of the battery in a day.
Meanwhile as far as inputs go, the side button is roughly analogous to the power button on a smartphone, but with a friends list and Apple Pay mapped to the button as well. The Digital Crown is roughly analogous to a home button, but with a scroll wheel attached. In my experience, the Digital Crown isn’t manipulated with a twisting motion, but a sliding motion with a single finger similar to a scroll wheel.
Handoff works well with the iPhone, although it’s often difficult for me to remember to swipe up to activate Handoff when TouchID makes phone unlock almost instant. You are still able to use handoff via the multitasking drawer on your iPhone, but that requires a number of extra steps that can be slower than simply opening an app and navigating to where you need to be. I also find it a bit odd that Apple Watch doesn’t have a multitasking interface like iOS does, but given how rare it is that I attempt to switch to another app with the use of the double press interface I suspect that this is more of a fast app return switch than a multitasking switch.
Finally, "Hey Siri" works well in terms of activation, but it's really kind of disappointing that the hotword detection doesn't work with the display off. I suspect this is due to power requirements as I haven't seen any other wearable have screen-off hotword detection, but it would definitely be great to see such a feature in the future.
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name99 - Monday, July 20, 2015 - link
Regarding ARMv7k, check out the following story:http://arstechnica.com/apple/2011/09/support-for-q...
Note the date --- Sept 2011. Further evidence that Apple plans these things a LONG time in advance,
(Relative to which, it is interesting to note that over the past month there has been a flurry of activity by Apple people on working LLVM targeting M-class processors. Maybe Apple are planning more IoT peripherals in a few years, or maybe they want to stick a small MPU in every Beats headset for some reason?
Or maybe they are moving from whatever they use today for PMU and sensor fusion on iOS/Watch to an M-class core?)
hlovatt - Monday, July 20, 2015 - link
First, thanks for a great review. Excellent to have such detail.I don't wear a watch so won't be getting one. However I know 4 owners who are all very happy. They all previously owned smart watches, Garmin, Pebble, Fitbiz, etc. and universally prefer the Apple Watch. The tap thing sounds like a gimmick, but just try it - it's really well done.
Gripe: If you hate Apple so much that you can't be rational just leave Anandtech. There are plenty of places were you can have a mutual we hate Apple session. You are spoiling the site for others who want to discuss tech. If you prefer some other product just buy it, don't sling insults at others that disagree with you. Get real the reviewers said they wouldn't recommend the 1st gen device and you go off saying they have sold out etc. Totally unfair to them.
name99 - Monday, July 20, 2015 - link
While investigating the CPU details in interesting (and thanks!!! for doing this) I think it's important to appreciate that the CPU is probably the least important thing about aWatch performance as it matters to the average person.There are IMHO three primary performance problems with aWatch today:
(a) There is far too little caching (in a very generic sense) so that third party apps (and some interactions with Apple apps) require communicating with iPhone. Much of this will disappear with WatchOS2; some of it may be an inevitable fact of life regarding how BT LE works and, in particular, the minimum possible latency when one side wants to talk to the other. But it's also possible that this latency could be reduced in future versions of BT by changing the rendezvous algorithm?
(b) The touch screen controller (I assume to save power) only seems to take initial sensor reading at around twice a second. The result is that the first time you touch the screen to scroll, there is an obvious halting until the system sort of "gets it" and starts smoothly scrolling. This is obviously a touch screen issue because using the digital crown (when that is feasible, so for vertical rather than horizontal scrolling) acts immediately and smoothly. The fix, presumably, is to ramp up the rate at which the touch screen controller does its initial sensing, but who knows what the power implications of that are.
(c) The heart rate sensor is on "full-time" (which means, I don't know, sensing once every 10 seconds?) when you are in the Workout app, but otherwise runs at a really low rate (once every ten minutes?) At least the way I use my aWatch, I'd prefer a higher rate.
I'm guessing that Apple was overly cautious about battery life in WatchOS1, and now that most people understand what to expect, and have about 40% battery at the end of the day, they can afford to bump up the sampling rates for all these different things (touch screen, heart rate, maybe even BT LE) and if that moves the battery life down to 20% battery at the end of the day, that's a pretty good tradeoff.
But nowhere in any of this is CPU performance actually an issue. I can't think of anywhere where CPU or GPU performance affect the experience.
name99 - Monday, July 20, 2015 - link
A few comments about fitness:The primary thing using the Workout app does, as far as I can tell, is switch to ongoing (rather than coarse) monitoring of heart rate and position, which is useful but not essential. However it DOES also give you a nice display of whatever you consider important. My Pebble used to kinda sorta track steps and thus calories, but the fact that the watch tracks and displays heart rate on the Workout app screen is actually really useful. With the Pebble I'd kinda slack off when doing a run or step climbing being that's only natural, but when your heart rate is displayed you have more incentive to keep pushing.
The workout app is also nice if you're trying to hit your calorie burn goal every day. If you get to say 10pm or so and are 150 calories short, you can set a calorie goal (rather than say a time goal or a distance goal) and then just start stepping while watching TV or whatever.
Two useful facts to know (which I don;t think you mention). You can launch Workout (or any app) through "Hey Siri launch workout" rather than navigating to the app screen. (It's also useful to know that Hey Siri as a way to start speech ONLY works when the screen is lit up. If you don't know this, it's maddening at first as half the time it seems to work and half the time it doesn't.
Also double-clicking the digital crown toggles between the most recent app and the watch face. I use it a lot to toggle between watch and workout.
Finally most readers are probably young and think the stand up stuff is dumb or pointless. It really isn't, at least for older people. I've got to the stage where, when I stand up I can feel a kind of stiffness in the muscles, you know that old person sigh when you get up. And I've found that since getting the watch and heeding the stand notices, that has pretty much disappeared --- it really does help older muscles to not get locked into no motion for two or more hours.
(Also if you find the standing irritating, it's worth noting that the watch wants you to stand for a full minute, with some motion. At first I just used to stand then pretty much immediately sit down. That's not good enough and it won;t give you credit for that. But if you stand and pace for a minute or so, it will always give a little ding and reward you with credit for the stand.)
The one thing I wish (there is so much we can all want them to add to WatchOS2 and then WatchOS3) is a data broadcast mechanism. In particular, if the workout data could be displayed simultaneously on a phone (placed near a TV or on a step machine control panel) that would be much more comfortable than having to flick the wrist every minute or so to check one's heartbeat. Oh well, in time...
navysandsquid - Monday, July 20, 2015 - link
I've never seen such a butthurt bunch of people. Almost every review on the internet give the apple watch a favorable review. Maybe you guys should stop letting you hate consume you. Anandtech has done one of the most indepth review of the apple watch. Which they do with most products. If you don't like apple products don't read the reviews. Your pathetic for even comments such ignorant things like "Watch under 9 days of battery life is unacceptable" Like please name a watch device with this much capability that runs longer then a couple days. oh wait you cant. I've had the watch for about 2 months and this review is spot on weather you like apple or not. Anandtech is a good review site. So just look in the mirror and say "Why do I hate them so much" Let me answer that for you. You don't like paying for what you get. Wait let me rephrase that. you do like paying for what you get your just to cheap to pay for quality. so p1ss of and buy yours self a Samsung smart watch for 149$ and let it collect dust lol I'm donename99 - Monday, July 20, 2015 - link
"Glances are well-executed and a useful feature, but I don’t really get the point of integrating heart rate monitoring into a glance or similar cases of app information"The authors appear unaware that you can customize glances. Go to the Watch app on iPhone and look around. You can both hide glances you find unimportant, and rearrange those that you want to use. Once you've done this, you can basically prioritize so that the most important stuff is in complications, while second tier stuff lives in glances, and third tier stuff requires an app launch.
name99 - Monday, July 20, 2015 - link
"Moving on to the saturation test, we can see that Apple has put a huge amount of effort into calibrating these displays, which is somewhat surprising given that one might expect wearables to not be all that critical when it comes to color accuracy."A persistent (and STILL not fixed) problem with the Apple ecosystem is that the faces of contacts display slightly differently on OSX vs iOS. There are outright bugs in the system (.psd photoshop files get incorrectly cropped on iOS, and different gamma is applied on OSX and iOS) but these may be fixed with the new Contacts framework of iOS9/OSX 10.11.
Point is --- your eye is actually remarkable sensitive to these apparently very slight deviations, at least when it comes to faces. So it makes sense for Apple to line up their hardware so that when they (at LONG FREAKING LAST!) get their software act together, the face photos do look identical across the line.
(And BTW how long will we have to keep typing in triples like iOS10/OSX 10.12/WatchOS3? At some point, and I think we're reaching that point, it's time to just refer to AppleOS 2015 followed by AppleOS 2016 followed by ...)
aryonoco - Monday, July 20, 2015 - link
I am not an Apple hater, and I am very curious in the Apple Watch and the whole wearables category. However I agree with those who say that this review was below Anandtech's standards. Overly wordy, with too little information. I don't think I have ever said this about an Anandtech review before, but after reading this, I really don't think I learned a single thing that I didn't know going into the review.whiteiphoneproblems - Monday, July 20, 2015 - link
Without wanting to "pile on," I agree that this review could have been 1/3 the length, and 3x as helpful. I usually look to AT for the "best" review of any mobile device, but I would not say that is the case with this particular review. Most other Apple Watch reviews I've read have been more useful. (I think it comes down to editing.)nrencoret - Monday, July 20, 2015 - link
+1 on that. I think you nailed the fact that Anandtech's succes is after reading an article, you always come out at the end a bit (or a lot in some cases) smarter. This review breaks the trend.