The most secure phones on earth

March 20, 2014, 3:06 PM UTC
Illustration: viktor Koen

There’s no such thing as a fully tamper-proof phone, but two new mobile devices come close.

Boeing is developing a smartphone, dubbed Black, that would make even the likes of James Bond’s gadget man, Q, drool. Try to take it apart and it self-destructs. It also has built-in disk encryption, which protects stored data by converting it into garbled code. Boeing’s staying mum on how much the device will cost and when and where it will be available, but the phone won’t be in your local store — it’s intended for the government contractor’s defense and security customers.

A different phone, called Blackphone, caters to everyday consumers — or at least those willing to pay $629 for a device that lets them initiate encrypted calls, text messages, and file transfers. The Blackphone keeps mobile web searches anonymous and allows those who use it to block everyday applications like Facebook from tapping into their location, contacts, and other data. Its maker, a new company called SGP Technologies (a joint venture between the secure-communications firm Silent Circle and a small Spanish phone manufacturer called Geeksphone), says it will be available for sale in June. At least one carrier — the Dutch mobile operator KPN — has committed to selling the device, with more expected to sign on by this summer’s launch. The company is also at work on a tablet with similar privacy controls.

Both phones run on customized (and supposedly more secure) versions of the Android operating system — ironic, since the business model of its maker, Google, is predicated on the ability to harvest and share customer data. Still, Android is the world’s most popular mobile platform, powering hundreds of millions of devices in more than 190 countries. The potential audience for an ultrasecure operating system is massive. “This [phone] is for more than a handful of guys in tinfoil hats,” says Toby Weir-Jones, managing director of SGP Technologies.

Of course, the new mobile phones have their limits. “Even with a ‘hardened’ device, you still have to run the same apps as anyone else using an Android [phone],” says Dionisio Zumerle, an analyst for Gartner. “And as the number of apps is not decreasing, the malware issue is not going to fade away.”

So what’s a sure-fire way to guarantee that you have a private and secure mobile experience? Turn the thing off.

This story is from the April 7, 2014 issue of Fortune.