Learn the basics of using mobile phones security.
Be aware that your smart phone is generally tied to your identity. This happens through billing, account services or SIM card registration. Your phone can also reveal your location.
Encrypted messaging tools do not protect you from sharing this, but they do help protect the content of your communication.
ChatSecure by The Guardian Project integrates with desktop chat Clients like Jitsi and Pidgin (using Gchat or Jabber/XMPP) and adds end-to-end encryption and the ability to send encrypted files, photos and audio.
With csipsimple you can also make secure calls (such as from Ostel).
RedPhone (for voice) and TextSecure (for SMS) by WhisperSystems are good, but both you and the person you are communicating with must be on Android (with these tools installed) in order for these tools to work.
Orbot by The Guardian Project and the Tor Project allows you to access the web, instant messaging and email without being monitored or blocked by their mobile internet service provider. For more information, refer to the Orbot lesson
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