Apple Platform Security
- Welcome
- Intro to Apple platform security
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- System security overview
- Signed system volume security
- Secure software updates
- Operating system integrity
- Activating data connections securely
- Verifying accessories
- BlastDoor for Messages and IDS
- Lockdown Mode security
- System security for watchOS
- Random number generation
- Apple Security Research Device
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- Services security overview
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- Apple Pay security overview
- Apple Pay component security
- How Apple Pay keeps users’ purchases protected
- Payment authorisation with Apple Pay
- Paying with cards using Apple Pay
- Contactless passes in Apple Pay
- Rendering cards unusable with Apple Pay
- Apple Card security
- Apple Cash security
- Tap to Pay on iPhone
- Secure Apple Messages for Business
- FaceTime security
- Glossary
- Document revision history
- Copyright
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Express Cards with power reserve
If iOS isn’t running because iPhone needs to be charged, there may still be enough power in the battery to support Express Card transactions. Supported iPhone devices automatically support this feature with:
A payment or transit card designated as the Express Transit card
Access cards with Express Mode turned on
When the side button is pressed, the battery icon shows that power is low, and text indicates that Express Cards are available to use. The NFC controller performs Express Card transactions under the same conditions as when iOS is running, except that transactions are indicated only with haptic notifications (no visible notification is shown). On iPhone SE 2nd generation, completed transactions may take a few seconds to appear onscreen. This feature isn’t available when a standard user-initiated shut down is performed.