You may have heard of a new Israeli developed iPhone/Android app called Viber. Viber is an app that allows you to make free calls between other Viber users in a manner not unlike Skype; the key difference is that with Viber you don’t even need an account. Viber looks through the contacts on your iPhone, identifies those that use Viber too, and offers them as potential call targets. All you need to do is install the app; sounds great, doesn’t it?
I truly hope none of my friends uses Viber, as I don’t want my personal details running around the world and out of my control. The fact that Viber can acquire my information without my consent and get away with it is testimony to privacy legislation’s lag behind the times in this age of the Internet.
Update - 17/2/2011:
It has been brought to my attention that my concerns were already raised by others (here) and addressed by Viber (here, for example).
The main question is how well the privacy concerns are addressed. My impression is that Talmon Marco of Viber seems genuinely honest and open about balancing between an effective solution on one side and privacy concerns on the other. The matter is open for interpretation, though: there is always the question of just how cynical you are about the way companies will find creative ways to abuse your privacy. I know I can be very cynical there: for example, I have seen and heard a lot from Google with their "do good" mantra on one hand, and their eavesdropping on unencrypted Internet traffic on the other.
With Viber's clarifications, though, it seems to me as if using Viber places you in similar spheres to using Gmail or Hotmail to manage your contacts and on much better grounds than using Facebook. Which brings me to say this:
I stand corrected. I consider the explicit warning I issued above regarding the use of the app to be wrong; Viber seems as safe as most other commonly used web communication facilities, if not more.