uses an integrated computer described as a System in Package (SiP, for short) inside the Apple Watch. The SiP includes the main processor (the main engine that drives the watch’s performance), along with memory, storage, support processors for wireless connectivity, sensors, and input/output tech. Yes, that’s a lot of geek speak, which you don’t need to know about to use the watch.
With Apple Watch Series 7, the company is using a new chip called the S7, which can provide wearers all-day battery life yet still power the larger, more advanced watch display.
Apple Watch indeed houses a good number of wireless radios beneath its surface, including Bluetooth, Wi-Fi, GPS, and NFC. To understand what they do, check out the following sections.
Bluetooth 5.0
Bluetooth makes a local wireless connection between two or more devices. Just as your wireless headset is paired with your smartphone so you can make hands-free calls, Apple Watch wirelessly communicates with a nearby iPhone to let you see texts on your watch, receive phone calls, control your music on your phone, and more. Bluetooth 5.0 works with devices up to 800 feet away (about 240 meters), which is significantly farther than in earlier versions. If you have an Apple Watch that supports cellular connectivity and pay for the service, you can perform many of these features — making calls, sending texts, and accessing online music — without having an iPhone nearby.
Wi-Fi
Even if you don’t have a cellular model, Apple Watch features Wi-Fi, which gives it online connectivity even when no iPhone is in sight. As long as you’re on a wireless network, such as your home’s Internet connection or a coffee shop’s hotspot, you can access such information as email, live sports scores, mapping information, and so on. A feature called Continuity — introduced in iOS 8 — allows you to receive messages and take calls on multiple iOS devices (such as answering a call on your iPad) as long as you’re in range of your Wi-Fi network, and Apple Watch has this feature too. See Chapter 5 for details on how to take advantage of Bluetooth and Wi-Fi connectivity.
Cellular
As I mention previously in this chapter, newer Apple Watch models (Series 6, 7, and SE) are available as GPS or GPS + Cellular. As you can guess, the GPS + Cellular watches cost a little more, but they let you make a call, send a text, and stream Apple Music from your wrist — all without your iPhone. You’ll need to pay your mobile phone provider an extra amount per month (usually about $10) to activate the eSIM inside Apple Watch. That is, you don’t need to insert a physical SIM card, like the one in your iPhone, to access the LTE and UMTS cellular bands.
Be aware, however, that no Apple Watch model supports worldwide roaming. Business travelers can purchase Apple Watch models for specific locales, such as Europe, Asia Pacific, and mainland China.
Beginning with Apple Watch Series 5, emergency calling works in countries outside the United States (see Chapter 5).
NFC
NFC (near-field communication) is a short-range radio technology (like Bluetooth) that has numerous applications but is most commonly associated with mobile payments, similar to waving or tapping your iPhone on a contactless terminal at retail locations (or a compatible vending machine) to make a secure purchase. Apple Watch also uses NFC to make a digital handshake with the terminal to complete the transaction. Yep, it’s all in the wrist. This feature is part of Apple Pay, Apple’s mobile payment solution for secure cash- and cardless payments. Check out Chapter 10 for more on Apple Pay.
GPS
Except for the first Apple Watch (Series 1, from 2015), Apple Watch has an integrated GPS chip to identify its location on Earth down to a few meters of accuracy. Therefore, when coupled with mapping applications, GPS can help you see your location on a map, get directions from point A to point B, look for local businesses of interest, and more. GPS can also help with tracking fitness data when measuring steps won’t help (such as in cycling). Along with the accelerometer (discussed next), built-in heart rate sensor, and Wi-Fi, Apple Watch’s GPS can help measure distance traveled. Jog on over to Chapter 8 to learn more about the Activity and Workout apps.
Ultra Wideband (Apple Watch Series 7 only)
While there aren’t a lot of use-cases for it yet, Apple added Ultra Wideband (UWB) technology to its Apple Watch Series 7. Similar to iPhones with UWB (beginning with iPhone 11 in 2019), this feature provides more precise location and spatial awareness. As you’ll see in Chapter 10, you can unlock a compatible car without even having to hold the iPhone or Apple Watch near the door lock.
Accelerometer, gyroscope, barometric altimeter, and compass
Like other smartwatches and activity bands on the market, Apple Watch has an accelerometer that measures movement, whether you’re lifting the watch to your face to turn on the screen; lowering your wrist to decline a call; or calculating fitness activities, including steps taken (like a 21st-century pedometer), total distance traveled, time spent exercising, and estimated calories burned. Beginning with Apple Watch Series 3 (2017), the watch also has an integrated barometric altimeter for measuring elevation (counting the steps you climb or descend) as well as calculating altitude for those who ski, hike, or climb mountains. Beginning with Apple Watch Series 6, the altimeter is always on, providing all-day, real-time elevation data on your wrist.
With the Apple Watch’s accelerometer and gyroscope sensor, Apple Watch Series 4 (2018) and newer models can detect whether you’ve fallen, and you can initiate a call to emergency services (or dismiss the alert). If you’re unresponsive after 60 seconds, Apple Watch automatically places the emergency call and sends a message with your location to your emergency contacts. Note: This feature is different from speaking to a live operator if you call, as you would with a service such as Philips Lifeline, but this feature is very handy to have on your wrist nonetheless (and you have no monthly fees to worry about).
A compass has been added to Apple Watch Series 5 and Series 6 models, always pointing you north inside apps like Maps, and there’s a dedicated Compass app too. (Cue the song “Go West” by the Pet Shop Boys or the Village People first!)
Heart-rate sensor
A custom heart-rate sensor included with Apple Watch helps you in two ways.
Gauging your exercise
