The likelihood that the NSA is interested in stealing anyones bitcoin private keys is smaller than winning the lottery every month. Although that doesn't mean they don't have the means to do it, which I believe is the title of this thread if I’m not mistaken. Someone could figure out how to exploit these backdoors...which some have done in the past. Luckily they were presented as opposed to used.

Good thing the majority of security conscious people don't keep their coins on a phone anyway they use Armory, paper wallets, etc.