Yes, NSA can specifically target iPhones, which I think happens by backdooring the computer which is used to sync the device. One of the NSA slides had a private photo from an iPhone of 'a former senior government official of a foreign country'. http://www.spiegel.de/international/world/how-the-nsa-spies-...
Which is completely different scenario than "the iPhone being backdoored". You don't have to sync your device to a computer that is online, except for the first activation.
