iGo Incognito 

iGo Incognito - Secure communications using a public key infrastructure and the Advanced Encryption Standard (AES). Supports rich voice/text messages, offline and online messages, private chats, open forums, file transfer and more...
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Utility Phone 

FREE Worldwide PC-to-PC communications using: voice, video, online/offline text messaging, text chat and file transfer, all secured using AES 256 bit encryption. Other features include activity notifications and privacy mode.
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