Guard Your Privacy

iOS offers many tools to help you protect your privacy, and in this chapter I explain how to take advantage of them.

Set a Passcode

Everyone should use a passcode. The passcode protects your photos, messages, browser history, and more from prying eyes. Here’s how to configure it:

1. Go to Settings > Touch ID & Passcode (or just Settings > Passcode).
2. Tap Turn Passcode On.
3. Enter a passcode.
4. Enter the passcode again to verify.
5. Consider enabling Settings > Erase Data. This feature automatically erases everything on a device after ten failed passcode attempts. If you recover the device, you can restore it from a backup, though that might be difficult or impossible while traveling.

Set up Touch ID

Touch ID, available on newer iPhones and iPads, lets you scan your fingerprint on the Home button instead of typing a passcode. In many cases, it also replaces your having to enter a password, such as the one that goes with your Apple ID.

If you have a Touch ID–equipped device, you were prompted to set up Touch ID when you set up the device. But in case you skipped that step, or want to edit your settings, here’s how:

1. Go to Settings > Touch ID & Passcode. (If you see only Settings > Passcode, either your device lacks Touch ID hardware or something is wrong with your device.)
2. Enter your passcode, if prompted.
3. Tap Add a Fingerprint.
4. When prompted, place your finger on the Home button (without pressing it), lift your finger up, and repeat until scanning is complete.
5. iOS then prompts you to scan the edges of your finger. Follow the onscreen instructions.
6. Repeat for each finger you might want to use to unlock your device. You can scan up to five digits; I recommend scanning at least both thumbs and your primary index finger.

After setup, it’s a good idea to name each finger by tapping its listing in Settings > Touch ID & Passcode and entering a name into the text field.

To delete a Touch ID fingerprint, open Settings > Touch ID & Passcode, slide the fingerprint’s entry to the left, and tap Delete. Or, tap the entry and tap Delete Fingerprint.

Set Up Find My iPhone

I strongly encourage you to enable Find My iPhone in Settings > Your Name > iCloud > Find My iPhone.

Then, if you ever lose your device, you can erase it remotely (or possibly even find it) from iCloud.com or the Find My iPhone app on a different Apple device signed in to the same Apple ID or grouped with your lost device through Family Sharing (see Use Find My iPhone and my TidBITS article Setting Up and Using Find My iPhone).

But the most important reason to enable Find My iPhone is that it also activates Activation Lock, which makes it extremely difficult for any thief to use or resell your device.

Understand Privacy Settings

Tap Settings > Privacy to access many options for securing your privacy. Let’s look at the high points:

• Disable ad tracking: If you do nothing else, you should tap Advertising (way at the bottom) and make certain that Limit Ad Tracking is on. If this switch is off, advertisers track information about you (anonymously) and use it to serve personalized ads within certain apps.
• Analytics: There are three switches under this listing: Share iPad Analytics (with Apple), Share With App Developers, and Share iCloud Analytics (with Apple). Apple and app developers use these to help improve their products, and your information is protected with differential privacy. So feel free to leave them on without threatening your privacy, but if you’re truly worried, turn them off.
• Microphone: It’s a good idea to check this setting every now and again to make sure no apps are listening in without your knowledge.

• Enable or disable location tracking: Tap Location Services to specify which apps can see your geographic location.

  You can turn Location Services off entirely, but that’s a bad idea—you won’t be able to use the Maps app, for example. You’re better off adjusting location services on a per-app basis, focusing on apps that don’t need to know where you are or don’t need to know all the time. For instance, a weather alert app may need to know your location all the time, but Maps only needs to know while you’re using it. And a calculator app doesn’t need to know at all!

• Per app: The Settings > Privacy screen has several options to limit access to app data from other apps. For example, tap Photos to see a list of apps that have access to your photo library.

Learn About Two-Factor Authentication

Mere passwords are no longer sufficient to guard your Apple account; you also need a second factor—an arbitrary code sent to a secondary device.

iOS 8 introduced two-step verification, but that was only a step en route to full two-factor authentication, which Apple introduced in iOS 9. In iOS 11, you can set up two-factor authentication directly from an iOS device, but you have to disable two-step verification if you enabled it in the past.

Disable Two-Step Verification

If you still have two-step verification enabled, you’ll have to disable it before turning on two-factor authentication:

1. Go to appleid.apple.com and log in with your Apple ID.
2. If you’re on a desktop, click Edit under Security.
3. Choose Turn Off Two-Step Verification.
4. Choose Turn Off Two-Step Verification again at the prompt.
5. Create new security questions and answers when prompted.
6. Enter your birthday when prompted.
7. Enter a secondary rescue email address when prompted.

Enable Two-Factor Authentication

Next, you’ll want to enable two-factor authentication to secure your account:

1. On your iOS device, go to Settings > Your Name > Password & Security.
2. Tap Set Up Two-Factor Authentication.
3. Tap Continue.
4. If any of your devices are running operating systems older than iOS 9 or 10.11 El Capitan, you will be warned that they’re not ready for two-factor authentication. Don’t worry, you can still authenticate with older operating systems as long as you append the verification code to the end of your Apple password. Tap Turn On Anyway to proceed.
5. Enter the phone number you want to use to verify your identity, and whether you prefer a text message or phone call. Tap Next.
6. Enter your Apple ID password. You should also receive an email informing you that two-factor authentication has been enabled.
7. Enter your device passcode.

Use Two-Factor Authentication

When you authenticate one of your other Apple devices, Apple sends a notification to other devices that are already authenticated.

Tap Allow on the authenticated device to see a 6-digit verification code. Enter that code on the device you want to authenticate to complete login. Tap OK on the already authenticated device to dismiss the code.