com.apple.developer.accessory-transport-security
An entitlement that enables your app extension to exchange cryptographic keys with an accessory.
Discussion
If your app implements AccessoryTransportSecurity in an app extension, the framework requires the extension to have this entitlement with a value of true in its signature.
For more information, see Receiving iOS notifications on an accessory.
For information on adding entitlements to your app, see Adding capabilities to your app.