How to send encrypted messages to iOS, Android for free

While Silent Circle's encrypted devices and services look tempting, there are now end-to-end encryption services on the market available without spending a cent.
In a post-Snowden era, privacy and security have become hot topics -- but encryption often comes at a premium. Now, however, you can send end-to-end encrypted messages from iOS to Android devices for free.
On Monday, Open Whisper Systems announced the launch of Signal 2.0, with support for TextSecure private messaging. The free app allows users to send end-to-end encrypted group, text, picture, and video messages between Signal on iPhone and both RedPhone and TextSecure on Android, with the added bonus of removing SMS and MMS fees, ZDnet reported.
A strength of the app -- beyond obvious end-to-end encryption -- is how the app uses your existing phone contacts and address book and organizes your conversations in a simple flow format, similar to a messaging client with push notifications. With a clean interface and no separate account usernames or passwords to remember, the app is likely to appeal to the general public and users who want additional privacy but are not sure which encryption to use or how to set up more complex alternatives.
"We cannot hear your conversations or see your messages, and no one else can either. Everything in Signal is always end-to-end encrypted, and painstakingly engineered in order to keep your communication safe," Signal says.
Both Signal -- suitable for iOS devices -- and its Android counterpart TextSecure use end-to-end encryption protocols and store messages locally in an encrypted container. Messages sent over the WhisperSync server are encrypted, but traditional SMS messaging will be still monitored by your carrier.
Signal is the brainchild of developers Frederic Jacobs, Christine Corbett, and Tyler Reinhard, and has been released for free to the open-source community via Github, which paves the way for improvement and verification by other security professionals.
The free software gives mobile device owners the option of encrypting calls and text messages without having to pay monthly subscription fees. There are premium options available on the market, such as the Blackphone. The handset, designed with security in mind, is based on a custom Android operating system dubbed PrivOS and includes encryption services such as Silent Text and Silent Phone, which are subscription-based.
The secure communications firm announced the launch of its second-generation Blackphone product line at Mobile World Congress in Barcelona, Spain this week.