By Jason Snell

February 19, 2015 10:50 AM PT

Apple Watch: What We Know

Note: This story has not been updated for several years.

This time next year, we’ll probably all be wondering how we got by without our Apple Watches, but here and now there’s still plenty that we don’t know about the device Cupertino wants to put on your wrist. The crack Six Colors team (Jason Snell and Dan Moren) has assembled the sum total of human knowledge about Apple’s wearable device, or at least a reasonable facsimile. We’ve updated this document a few times, most recently after Apple’s March 9 event.

(If you’ve got a question, fill out this form and we’ll take those questions into account for future updates!)

When does the Apple Watch come out?

April 24 is the date! You’ll be able to pre-order the Apple Watch beginning April 10, and you’ll also be able to go to Apple retail stores and get a look at them beginning that day. Then, on April 24, they’ll be available to Apple customers in Australia, China, France, Germany, Hong Kong, Japan, the United Kingdom, and the United States.

How much am I going to pay for this thing?

Well, that depends on how much you’re willing to spend. If you’ve got $349, you can pick up the 38mm aluminum-and-glass Apple Watch Sport with a colored “fluoroelastomer” band sport band. On the other hand, if money is no object, the top of the line gold-and-sapphire Apple Watch Edition will set you back a pretty penny at $17,000. In the middle of the range is the stainless steel Apple Watch, which runs from $549 to $1099, depending on your choice of bands.

Do the three versions differ in what they can do?

Nope! This is all about materials: the metal of the case, the type of glass on the face, and the expense of the accompanying bands.

So there are three versions… but what about colors?

What indeed. Each of the three editions comes in a choice of two colors: the Sport in silver and space gray, the standard version in stainless steel and space black stainless steel (so space is apparently now both black and gray), and the Edition model in yellow gold or rose gold.

What about sizing? My wrists are beefy/delicate.

There are actually two different sizes of the Apple Watch: a 38mm case and a 42mm case. (That’s for each model, which means, for those of you keeping track at home, 12 distinct Apple Watches.) Which one you’ll want mostly depends on how big your wrists are. We imagine you may want to try them on before you decide, so you may want to plan on visiting an Apple Store to see one yourself. You can also fire up the Apple Store app on your iPhone and see the two watches at actual size.

Many of the bands also come in different sizes, so Apple provides a sizing guide to help you figure out just which one you’ll want. Plus, of course, you can always print out a paper version to tape to your wrist.

I’m picky about watch bands. Will the Apple Watch satisfy me?

Apple has announced six different band styles: a traditional metallic link bracelet, a rubberized sport band, leather with classic or modern buckle, leather loop, and the magnetic woven stainless-steel Milanese loop. And of course, within those styles there will be color and material variations. There will be a lot of bands to choose from, which put together with different watch variations means there are 38 models to choose from. You can probably find at least one you like.

Also, the bands are designed to slip on and off the Apple Watch itself with a button press, so you can easily swap from a sport band to a high-fashion model when it’s time to leave the gym and head to the opera, or the symphony, or anywhere else you’d never be caught dead wearing a watch with a sport band.

Does the Apple Watch let me pick from different watch faces?

What good would a watch with a Retina display be if it didn’t let you customize the face? Yes, the Apple Watch will come with “a variety of faces,” including traditional chronograph designs with digital hands, ones with numerals and snazzy graphics, and even a Mickey Mouse model if you want a throwback to when you were eight years old.

Each of the faces is meant to be customizable, too, so that you can modify the colors and even add or remove design elements (fittingly called complications) until the face contains just what you want to see. Which is good, since at launch the Apple Watch won’t support additional watch faces supplied by outside developers. (We fully expect that to happen eventually, but not at launch!)

Enough about how the thing looks… what does it do?

Lots, from what we can tell—in fact, a lot more than we really expected the first model of a new product line to do. The Apple Watch can handle notifications, health and fitness functionality, and, of course, act as a watch. It can even run very limited types of third-party software.

Will the Apple Watch run my favorite apps?

It’s a complicated question. Apple Watch will come with numerous apps from Apple, including: Weather, Calendar, Camera Remote, Phone, Mail, Stopwatch, Clock, Music, Maps, Fitness, Messages, iTunes Remote, Photos, Passbook, Settings, Stocks, and more.

It will also support apps from independent developers via something called WatchKit, but in two stages. At launch, third-party iPhone Apps will be able to project parts of their interface onto the Watch via Bluetooth. These projections will be simple, and connected directly to the program that’s running back on the iPhone. Think of them as very simple remote controls for things that are happening on your iPhone.

At some point—possibly by the end of the year—Apple says it will open up the Watch to full-fledged Watch apps, ones with code that actually runs on the Watch itself. These apps will be standalone and more fully functional, like the Apple-built ones that will ship with the Watch.

This approach makes sense. Apple’s own programmers are still learning the ins and outs of this new device. It would probably be asking too much for them to be, simultaneously, rolling out tools for third-party developers to build Watch apps. Instead, Apple’s offered an interim approach while its own developers learn how to develop Watch apps. Then they’ll roll that capability out to the eager third-party development community.

There are a ton of fitness-related wearables; what’s the Apple Watch’s approach?

Well, like your Fitbit or Jawbone Up, the Apple Watch tracks your steps. But it also takes a more holistic approach, rather than simply feeding you numbers. The built-in Activity app tracks how much you move (and thus how many calories you burn), how many minutes of brisk activity you’ve done, and how long you’ve stood.

Apple Watch displays this information in three concentric rings, and prompts you to “close the ring” for each of them in a day, so you can hit your goals. And as the Watch learns more about you and your activity, it can set reasonable goals for you to hit.

That sounds pretty chill—what if I’m working out?

There’s actually a separate Workout app for the Apple Watch, which gives you more detailed information, like time, distance, calories burned, pace, and speed. So if you’re a dedicated runner, you can use the information to track your workouts—and like in the Activity area, the Apple Watch can suggest goals for you based on what you’ve accomplished to date. It also all syncs back to your iPhone, where a new Fitness app lets you get more information, and links in with the Health app.

Wait, how does it find out all this stuff about me?

Because it’s packed with sensors. In addition to the same accelerometer and gyroscope that you’ll find in your iPhone, which measure body movement and steps, the Apple Watch also has a custom-built heart-rate sensor to track activity during workouts. It even uses your iPhone’s Wi-Fi and GPS to figure out how far you’ve moved around during the day, letting it better calculate how active you’ve been.

Okay, fitness is great and all, but I hear the Apple Watch also does notifications?

Yep. When you receive a text, email, or incoming call, your Apple Watch can alert you, and give you an opportunity to answer or dismiss it.

Alert me? Is this going to bug everyone around me by blaring my Journey ringtone?

Apple says it’s trying to make notifications unobtrusive, and to that end it’s created what it calls the “Taptic Engine.” Subtler than the vibration on your phone, the Taptic response is supposed to feel like somebody is tapping you on the wrist. Creepier? Maybe, but less obvious, we suppose. There are also sound alerts, but we presume that you can deactivate them if you prefer.

So do the notifications on the Apple Watch’s screen work like they do on the iPhone?

It’s a little more complicated than that. When a Watch app wants to notify you, it presents what Apple calls a “short look”— a brief item showing you what app is trying to notify you, with a hint about what the notification is about. If you lower your wrist, that notification vanishes.

But if you raise your wrist or even just hold it steady, the Apple Watch assumes you want more, and loads the “long look” notification, which is much more like something you’d find on the iPhone. A long-look notification includes information as well as buttons that let you interact with the information. The last button in every such notification is Dismiss, allowing you to get rid of the notification without interacting with it further.

Seems like there are probably times when I won’t want to respond to a message on my Watch. What then?

Good news: the Apple Watch supports a Handoff feature that lets you continue what you’re doing on your iPhone. Messages, emails, and calls can all be easily transferred from your Watch to your phone, so that you can compose a longer response or deal with tasks that the Watch isn’t suited for. (It’s unclear, however, if there’s any ability to Handoff items from the Watch to your Mac or vice versa.)

Is interacting with the Apple Watch more or less like the iPhone? We’re just tapping around on a little screen, right?

Yes and no. The Apple Watch is a touchscreen, yes, but it’s got a trick that the iPhone doesn’t: Like a Jedi master, it senses the Force. The Apple Watch has sensors around the display that can detect how hard you’re tapping the watch face, and the onboard software can interpret a soft tap differently than one containing a larger amount of force. When you tap with force, the Apple Watch reacts differently, providing you with contextually specific options instead of having you interact directly on the screen. Think of it as the wrist equivalent of a control-click.

What’s with the wheel on the side of the Apple Watch? Don’t tell me I have to wind this thing.

No, the wheel—called a Digital Crown—isn’t for providing your Apple Watch with extra power. It’s a clever additional input method for the device. The Apple Watch’s screen is small, limiting the room you’ve got to tap, swipe, pinch to zoom, and perform other gestures that seem natural on an iPhone. Apple’s partially compensated for this by augmenting the standard touch with the Force Touch, as we just described.

In addition to spinning the Digital Crown, you can also press it in. This makes the Digital Crown function as a home button. Press the Digital Crown and the Apple Watch will jump back to the home screen, full of app icons.

So if the Digital Crown is the home button, what’s the other button on the side of the Apple Watch?

This button accesses your Friends list, which is sort of like the list of people that you see at the top of the iPhone screen when you tap twice to enter the app switcher. Do you use that feature much? We rarely do, but Apple seems to love the concept because it’s dedicated an entire button to it on the Watch. When you tap the button, you’ll see a dial like interface showing you people you talk to frequently. From there, you can pick a person and then choose to call them, send them a message, or otherwise interact with them.

And there’s one other thing that button is good for. If you double-tap on it, it will activate Apple Pay.

Apple Pay works with the Apple Watch? How?!

Like we just said, you double-tap on the button to active Apple Pay. Then you can move the face of the Apple Watch toward a terminal that accepts Apple Pay and buy something. You don’t even need to take your phone out of your pocket. And here’s a crazy tidbit: As long as your Apple Watch is attached to your wrist, it will be authorized to use Apple Pay using the same accounts as your iPhone. But when you take the Apple Watch off, that authentication goes away; next time you go to use it, you’ll have to enter your PIN. That way, if someone steals your Apple Watch right off your wrist, they couldn’t buy anything with it using Apple Pay. (You can also remove all the payment cards stored on your Apple Watch via iCloud.com.)

How much power does this thing have? Is it like a tiny iPhone? What chip does it have inside?

The Apple Watch is a remarkably small gadget, and it’s powered by the Apple S1 chip, which the company says is a bunch of different subsystems all integrated into one module that’s “encapsulated in resin to protect the electronics from the elements, impact, and wear.” In other words, the entire brain of the Apple Watch is the S1, and it’s a sealed block. Being so small, it’s probably got some serious power limitations—especially given that it needs to draw a minimal amount of power in order to maintain battery life. But it’s a watch, not a phone. Expect animations to be fluid—and for the most heavy-duty processing work to happen on a connected iPhone, not the Apple Watch itself.

Given everything the Apple Watch can do, what kind of battery life can I expect from this thing?

Apple claims “all-day” battery life for the Apple Watch, where all-day means 18 hours. What’s that based on? “90 time checks, 90 notifications, 45 minutes of app use, and a 30-minute workout with music playback from Apple Watch via Bluetooth, over the course of 18 hours.”

Of course, depending on how much you’re using the Apple Watch, your battery life is going to vary—in some cases, significantly. Apple rates it for 3 hours of talk time, 6.5 hours of workout time, and 6.5 hours of audio playback.

What happens if it runs out of juice? Can I not even see the time anymore? What good is this darned thing in that case!?

Never fear. Apple’s created a Power Reserve feature to deal with just such an eventuality. Should the Watch’s battery drop too low, the Apple Watch will shift into a mode that just displays the time, and doesn’t do anything else. With that active, you can eke up to 72 hours out of the device, Apple says.

How do I charge this thing? I don’t see any ports.

The future, my friend, is magnets. Though Apple’s latest laptop may have bid adieu to MagSafe, it lives on in the Apple Watch. Though just because Apple’s calling the Apple Watch charger “MagSafe” doesn’t mean that it uses the same charger as your MacBook. It’s using the same concept—a charger attached to a magnet—but this is a different charger, round and flat, that snaps on to the back of the Apple Watch. (It also uses inductive charging capabilities that don’t require exposed contacts, hence the ability to make the Watch water resistant.)

Am I going to be waiting around a long time for this thing to charge, like overnight?

Charging time’s actually not too bad. Apple says about 1.5 hours will get you to 80 percent capacity, and roughly another hour will take you up to full. So overnight is plenty, but you can even just grab a short charge during your lunch break if you need to.

Given that the 42mm version is bigger, does it also have a bigger battery?

Apple’s mum on the exact differences; all it says is that “A 42mm Apple Watch typically experiences longer battery life.” We’re guessing that’s on the order of extra minutes, but less than an hour.

Does Siri work with the Apple Watch? And can I talk to the Watch in other ways?

Yep, the intelligent assistant has sensibly made the jump to the Watch. After all, you’re not going to be tapping on a tiny Apple Watch-based keyboard, so it only makes sense to, uh, talk to your Apple Watch, strange as it might look. There are a couple of ways to summon Siri: you can press and hold the Digital Crown, just as you would the Home button on your iPhone or iPad; or you can lift your wrist and say “Hey, Siri!” Then ask Siri to get you directions, send a message, or get your upcoming appointments.

And yes, Siri’s dictation feature is there as well, for when you want to send messages from your wrist without using the Apple Watch’s canned options.

Speaking of talking to my Watch, can I make phone calls, Dick Tracy-style?

If you must, you can. The Watch has a microphone and a speaker, so you can make and receive phone calls; you can also transfer those calls over to your iPhone for longer, or more private, conversations. And, in a really nifty feature, it’s easy to mute incoming calls by simply covering the Apple Watch with your hand.

So texting, emails, phone calls—seems like communication is a big part of the Apple Watch. What other options are there?

Communication is clearly a key area for the Apple Watch, given that dedicated Friends button. And beyond just emailing and texting, should your friends also have an Apple Watch, you can use the Sketch feature to draw little ephemeral images instantly sent to your friends’ Apple Watches, the Tap feature to have the Apple Watch tap their wrist (because that will not be distracting at all), and, of course, the probably-intended-to-be-sweet-but-somewhat-creepy option that lets you send someone your heartbeat.

I really like the look of those fancy link bracelet/leather straps, but I think I’m going to get the entry-level Apple Watch—will I still be able to buy other bands separately? Will they fit?

Let’s take the second part first. From what we can tell, the bands are indeed interchangeable—at least, between Apple Watches that are the same size. That is, a 42mm strap that works on the Apple Watch Sport should work on the Apple Watch Edition and vice versa. Sstraps meant for the 38mm model will not work on the 42mm version, given the physical difference in size, or vice versa.

You can also buy pretty much any of the bands after the fact (with the exception of the bands that come with the Apple Watch Edition and, it appears, the space black link bracelet); the prices range from $49 for sport bands to $449 for the silver link bracelet. So if you really want that fancy Milanese loop with your Apple Watch Sport, have at!

Do be aware that some of the straps have metal “pins” that are designed to match the case of the watches, though, so if you buy an aluminum Apple Watch Sport and want to class it up with a black classic buckle, your stainless steel pins might stand out slightly. Mix Your Watch is a great resource for mixing and matching, if you’re curious about specific combinations.

I’m a lefty, but all of Apple’s product shots show the Watch only in use by righties. Is this some sort of sinister plot? Am I going to be left out in the cold?

Good news! As Apple itself says, the Watch “can be set up to work on either your left or your right wrist.” We confirmed this at the Apple event back in September; the solution involves flipping the Watch over, so yes, the Digital Crown will be below the Friends button rather than above it, but otherwise, the Watch should work the same way.

You configure this feature via the Apple Watch app that’s included with iOS 8.2 and higher; you can specify which arm you’re wearing the watch on, and which direction the crown is pointing. Pick the most comfortable!

Is the Apple Watch water resistant? Can I swim with it? What about sweat?

Indeed it is. Tim Cook mentioned on his recent European tour that he doesn’t even take his off to shower, and Apple’s product page says that the Apple Watch is “splash and water resistant but not waterproof.” Specifically, it suggests you can “wear and use Apple Watch during exercise, in the rain, and while washing your hands, but submerging Apple Watch is not recommended.” At the Apple event in March we even overheard Cook himself telling someone that it’s good at being water resistant but “just don’t go diving with it.”

Further fine print says that the Watch has a water resistance rating of IPX7 under IEC standard 60529, which means that it can be submerged up to a meter underwater for 1 hour without letting any water in. Sounds to us like you could go swimming in it—sport band only, please!—but Apple doesn’t want to make a big deal of this fact yet.

Honestly, we had pretty much assumed that any device which markets itself with a Sport edition is probably at least modestly sweat resistant.

Either way, this guy seems pretty comfortable with it.

I’m coveting an Apple Watch, but I have an older iPhone. Will the Watch work with that? What about with my iPad?

Apple’s page says the Watch requires an iPhone 5 or later. Sorry 4s owners, but it may be time to look into an upgrade.

As for the iPad, the answer appears to be “no,” at least for now. That’s not shocking: both the Watch and the iPhone are meant to be carried around with you—the iPad, not so much. The iPad also isn’t listed as supporting in-store Apple Pay, so that’s a mark against it.

Wait, so if the Apple Watch relies that heavily on my iPhone, how well is it going to work if I’m away from my phone, say, if I’m out for a run? And how far away can I get before I lose contact?

With no built-in cellular networking of its own, it’s true that the Apple Watch’s functionality is going to be limited when your phone’s not nearby. The onboard fitness software ought to work fine, and there’s 2GB of onboard storage for music playback, but Siri probably won’t work, you won’t get notifications, and third-party apps probably won’t work either.

As to how far away you can get, we’re presuming that the communication with the phone happens primarily over Bluetooth LE, which has a range that can exceed 100 meters. That’s pretty far, so you should be able to, say, leave your phone in one room and walk into another without losing contact.

The Watch also has 802.11b/g/n Wi-Fi (all older protocols that use the 2.4GHz range). At the Apple event in March, the company implied that you can roam around your house and as long as your iPhone and Apple Watch are on the same network!

Either way, as anybody who’s spent a decent amount of time with Wi-Fi networks knows, your range for wireless signals depends on a number of factors, including what materials are in between the two devices. If you’ve got walls full of chicken wire, that’s going to lower your effective range.

We don’t know, however, if the Watch will warn you when you’ve lost contact with your phone, say, by giving you a tap on the wrist.

So there’s 2GB of storage for music? Is that all? What about photos?

Overall, the Apple Watch has 8GB of onboard storage, but most of that appears to be reserved for the OS and apps. 2GB are set aside for music, meaning that it works pretty much like an iPod Shuffle—you’ll use the Apple Watch app on your iPhone to pick playlists or tell your phone to fill it with a random subset of your music. 2GB is still enough for hundreds of songs, which should keep you occupied while you’re away from your more capacious iPhone.

According to leaked screenshots of the Apple Watch app (which appeared, undeletably, on all our phones with iOS 8.2), you’ll also be able to specify how much space you want to use for photos, up to 75MB. That may seem pretty small, but remember that the Watch’s displays, while Retina, have a resolution of just 272 x 340 for the 38mm version and 312 x 390 for the 42mm model. So your photos are going to be pretty small.

Wait, there’s music playback, but there’s no headphone jack! Am I going to listen to my tunes through the tiny speaker on this thing? Or will it support Bluetooth headphones?

There is a speaker—we know, because you can make calls and have the sound come through the Watch—so if you really want to listen to music on it, you may very well be able to.

But given how much Apple seems to care about music, we’d be pretty surprised if they wanted you to listen through the Watch’s own speaker. Fortunately, Apple says on the Apple Watch apps page that you can indeed pair Bluetooth headphones directly with the Watch.

Speaking of fitness, are the Apple Watch’s fitness capabilities good enough for tracking heart rate while I’m working out? Or is it really only intended to track basic activity?

Apple’s touting the fitness aspects of the Watch, including a dedicated Workout app that can be used when you’re biking, running, or working out in a gym. Given how central that is to the Watch’s functionality, it should definitely be able to handle your heart rate when you’re working out.

What if I already use a fitness app like Strava or RunKeeper—can I get my workout information from the Apple Watch into that app?

Well, the Workout app on the Apple Watch communicates with a Fitness companion app on the iPhone, and that Fitness app can in turn talk to the Health app that shipped as part of iOS 8. Third-party apps can access information from Health, but you may have to wait until developers update their software to take advantage of these new features.

So, the Sport is made out of aluminum and Ion-X glass, and the standard Watch is made from stainless steel and sapphire crystal. What’s the difference between those metals and glasses?

Well, for one thing, the Sport body is lighter than the stainless steel model. (However, the sport bands are heavier than some of the other bands, meaning that according to Rob Griffiths’ spreadsheet the lightest model with band is the 38mm Apple Watch with classic buckle.

The sapphire crystal may also offer more scratch resistance than the Ion-X glass, and be harder to shatter.

I noticed two small slots and a little hole on the side of the Apple Watch that doesn’t have the Digital Crown. What are those, some kind of access port?

Apple doesn’t specifically explain what they are, but we’d guess they’re some combinations of speaker and microphone. (It’s possible two of them are microphones, since that can make it easier to do noise canceling.)

If I misplace my Apple Watch, can I use my phone to find it? What about vice versa? Is there any security on the Watch itself to prevent someone from using it?

According to those same leaked screenshots, you can set a four-digit simple passcode or more complex passcode on your watch. (Which Apple says you’ll also need to enter every time you take your watch off, in order to protect your Apple Pay data.) You can also opt to have your Watch automatically unlock when you unlock your iPhone, as long as you’re wearing the Watch. And, as on the iPhone, you can have your Watch erase all the data on it after ten failed attempts.

We don’t know if you can use your phone to find your Apple Watch (hopefully it’s on your wrist!), but Apple does say that if you misplace your iPhone, you can ping it from the Watch.

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