BitTorrent has released new free apps for communicating securely. Bleep is available both as a freely downloaded iOS app on the iOS App Store, and as a Mac app that can be downloaded from the Bleep website. Both set up direct peer-to-peer encrypted communications that cannot be intercepted as no messages are ever stored in the cloud. There's not even a signup process, so nobody has to know you're using Bleep.
If you're sending text messages or photos, Bleep provides two ways of communicating: Whispers are text and image messages that disappear once they've been read, and Messages are stored locally on the device. Of course, Whispers can be bypassed simply by taking a screenshot of whatever's on the screen, but we're all smart adults, right? Except for politicians and celebrities... Voice calls are also available with that same peer-to-peer encryption in place.
Bleep is also available for Android and Windows.