UIRequiredDeviceCapabilities

This lets iTunes and App store know which device related features required for an app to run.iTunes and App store uses this info to prevent the users from installing the app on the device that does not support the required capabilities.

Key	Description
telephony	Include this key if your app requires (or specifically prohibits) the presence of the Phone app. You might require this feature if your app opens URLs with the tel scheme.
wifi	Include this key if your app requires (or specifically prohibits) access to the networking features of the device.
sms	Include this key if your app requires (or specifically prohibits) the presence of the Messages app. You might require this feature if your app opens URLs with the sms scheme.
still-camera	Include this key if your app requires (or specifically prohibits) the presence of a camera on the device. Apps use theUIImagePickerController interface to capture images from the device’s still camera.
auto-focus-camera	Include this key if your app requires (or specifically prohibits) auto-focus capabilities in the device’s still camera. Although most developers should not need to include this key, you might include it if your app supports macro photography or requires sharper images in order to do some sort of image processing.
front-facing-camera	Include this key if your app requires (or specifically prohibits) the presence of a forward-facing camera. Apps use theUIImagePickerController interface to capture video from the device’s camera.
camera-flash	Include this key if your app requires (or specifically prohibits) the presence of a camera flash for taking pictures or shooting video. Apps use the UIImagePickerController interface to control the enabling of this feature.
video-camera	Include this key if your app requires (or specifically prohibits) the presence of a camera with video capabilities on the device. Apps use the UIImagePickerController interface to capture video from the device’s camera.
accelerometer	Include this key if your app requires (or specifically prohibits) the presence of accelerometers on the device. Apps use the classes of the Core Motion framework to receive accelerometer events. You do not need to include this key if your app detects only device orientation changes.
gyroscope	Include this key if your app requires (or specifically prohibits) the presence of a gyroscope on the device. Apps use the Core Motion framework to retrieve information from gyroscope hardware.
location-services	Include this key if your app requires (or specifically prohibits) the ability to retrieve the device’s current location using the Core Location framework. (This key refers to the general location services feature. If you specifically need GPS-level accuracy, you should also include the gps key.)
gps	Include this key if your app requires (or specifically prohibits) the presence of GPS (or AGPS) hardware for greater accuracy when tracking locations. If you include this key, you should also include the location-services key. You should require GPS only if your app needs more accurate location data than the cell or Wi-fi radios might otherwise allow.
magnetometer	Include this key if your app requires (or specifically prohibits) the presence of magnetometer hardware. Apps use this hardware to receive heading-related events through the Core Location framework.
gamekit	Include this key if your app requires (or specifically prohibits) Game Center (iOS 4.1 and later.)
microphone	Include this key if your app uses the built-in microphone or supports accessories that provide a microphone.
opengles-1	Include this key if your app requires (or specifically prohibits) the presence of the OpenGL ES 1.1 interfaces.
opengles-2	Include this key if your app requires (or specifically prohibits) the presence of the OpenGL ES 2.0 interfaces.
armv6	Include this key if your app is compiled only for the armv6 instruction set. (iOS v3.1 and later.)
armv7	Include this key if your app is compiled only for the armv7 instruction set. (iOS v3.1 and later.)
peer-peer	Include this key if your app requires (or specifically prohibits) peer-to-peer connectivity over Bluetooth. (iOS v3.1 and later.)
bluetooth-le	Include this key if your app requires (or specifically prohibits) the presence of Bluetooth low-energy hardware on the device. (iOS 5 and later.)