As part of rolling out the first-phase of The Guardian Project, I will be writing short reviews of existing applications for Android-based mobile phones that share our general goals or desired functionality. The goal of Guardian, in short, is to enable safe and secure communication for activists, organizers and advocates working for good around the world through the mobile phones they carry in their pockets.

The Guardian project has no official relationship with these apps or their creators, but as we work towards developing our own unique software, we want to make sure to shine the spotlight on existing efforts that we admire and which are currently available. We’d also happily collaborate with any of them (or *you* if you are a developer reading this), and have them join our open-source efforts.

The first application is Walkie Talkie Push to Talk, which is a great alternative take on real-time VOIP or standard phone calls. Physical walkie talkie radios and Nextel-style PTT services have long been a valuable tool for many activists, and this application bring that capability to a global scale. Walkie Talkie can be used over GRPS, EDGE, 3G or Wifi networks, as well – whatever is available at the time.

Here’s a short description from the developer:

Walkie Talkie Push to Talk is a mobile application that allows walkie talkie style voice communications. Simply hold down the “Record & Send” button and speak. Messages can be sent to a group of people. Received messages are automatically played. If program is running, incoming messages arrive as soon as 15 seconds. If program is not visible, it polls in the background every 1 minute (to save battery).

The back-end messaging system used by this application is actual POP or IMAP, in other words email! If you utilize a secure IMAP/S connection with the application, then the voice communications are transmitted securely over the wireless network and Internet. If you use a service like Gmail (which offers secure IMAP access), then your access is hidden within the millions of other users accessing Gmail, as well.

Not drawing attention to your network traffic is often as important as securing your data. Also, while Gmail isn’t always the ideal service to use if you wish to retain full control of your data, it is much more difficult for an authority to block than a single proxy or a private server.

Learn more about Walkie Talkie and download it from the Android Market today.