But you can't listen to your music on the Apple Watch's built-in speakers — and probably wouldn't want to anyhow. Instead, connect a pair of Bluetooth headphones, or even a Bluetooth speaker if you're staying put. Just put your headphones into pairing mode, launch the Settings app on the watch, tap Bluetooth, and wait for the headphones to show up under the Devices heading. Tap to pair, and you're all set.
As with music, the Apple Watch spares some local storage space for photos. By default, it syncs photos you've marked as Favorites on your iPhone or in Photos for Mac, though you can select another album for it to sync. And like music, you can choose how much space to devote to storing photos locally: From 5MB (25 photos) to 75MB (500 photos). Since they're stored locally, you can always pull those photos up on your phone, just in case you want to remember what your loved ones look like in those trying moments when you can't get online.
While the lack of a network connections means you won't get any new information on your Apple Watch, much of the data that's been downloaded there is still active. So browsing through the Mail, Calendar, and Messages app will show you whatever information was current the last time you had a connection to your phone. You can read messages, browse appointments, and check your message history to your heart's content.
At a glance
Finally, while third-party apps and those that require an active data connection won't be too helpful when you're without your phone, many of the Apple Watch's glances will still be useful, albeit a bit stale. Most will continue to show whatever information was most recently retrieved, with a note about when exactly that Glance was last updated. Because sometimes old news is better than good news.
One of the Apple Watch's best features is that it brings Apple Pay to another device. Once you set up your cards using the Apple Watch app for iPhone, you don't need the iPhone around to make a purchase, since the Apple Watch has its own Secure Element to store your device's ID number. When it's time to make a payment, just tap the Apple Watch's button twice to bring your default card to the screen. (If you have more than one card, you can switch between them at this point.) Then hold your watch to the payment terminal — you probably have to point the screen down, away from you, but you'll hear a beep and feel a buzz when the transaction goes through.
Your Apple Watch will automatically lock if you take it off, which means that if you lose it or it's stolen, whoever has couldn't use Apple Pay unless he or she could unlock your watch with its passcode. You can optionally unlock the Apple Watch by simply unlocking your iPhone, so if you're paranoid about losing both of them at the same time, you might want to turn that option off in the Apple Watch app for iPhone. (It's in My Watch > Passcode, under "Unlock with iPhone.")
Granted, an Apple Watch without a data connection may not have quite the same smartwatch appeal, but at least there should be enough to do to tide you over until you're reunited with your iPhone once again.
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