Bluetooth stereo headphones and speakers
The iPhone 5s and iPhone 5c offer the same support for stereo-Bluetooth audio as the past few iPhone models. You can pair the phone with multiple Bluetooth speakers and headphones, using the AirPlay button in Control Center to choose which device to send audio to. If your speakers or headphones include AVRCP playback controls (play/pause, previous, next), you can use those buttons to control playback, and, depending on how the accessory was designed, you may also be able to adjust your phone's own volume level using volume buttons on the speakers or headphones.
Other audio accessories
Lightning-connector audio accessories, such as Griffin Technology's StudioConnect with Lightning and IK Multimedia's iRig HD, that work with the iPhone 5 will continue to work with the iPhone 5s and 5c. However, as with docks, if an accessory has a cradle or other physical design made specifically to fit the iPhone 5, it may not physically fit the 5c.
USB-based audio accessories, such as microphones, that currently work with the iPhone 5 using Apple's Lightning to USB Camera Adapter should also work with the iPhone 5s and 5c.
Apple's Lightning Digital AV Adapter and Lightning to VGA Adapter are compatible with both new iPhone models, letting you output video to a TV, projector, or other video device over HDMI or VGA, respectively.
Apple continues to restrict Lightning-connector video output to the company's own accessories. (At least as far as we know--we haven't yet seen a third-party Lightning-connector dock or other accessory that supports video out.) As with all Lightning-connector-equipped devices, Apple's Lightning to 30-pin Adapters don't support video, so you can't use the video features of older 30-pin-dock-connector accessories with either new phone.
Apple's Lightning to USB Camera Adapter and Lightning to SD Card Camera Reader are compatible with both new iPhone models. Similar products from third-party vendors should also work, provided they're licensed (see "iOS 7-related accessory issues," below).
Older 30-pin accessories
Both new phones can take advantage of Apple's Lightning to 30-pin Adapters to work with accessories that use the older 30-pin dock connector.
However, the same restrictions apply here as applied to the iPhone 5: Most audio and charging accessories will work fine, though very old docks that charge using FireWire circuitry won't charge your iPhone 5s or 5c. Neither adapter supports video, so if you've got a 30-pin accessory that provides video output--say, for showing your iPod or iPhone's video on your TV--that output won't work with either new iPhone. Finally, as with the iPhone 5, Apple's adapters don't support iPod-out mode, a special mode that lets particular accessories, such as car stereos and some whole-home-audio systems, display a version of your iPhone or iPod's menus on the accessory's own screen.
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