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Secure Iphone and Android Apps

A few years ago, Edward Snowden released secret NSA documents about their very aggressive massive data gathering efforts, spawned by the 9/11 terrorist attacks. It wasn’t until Snowden’s revelations that the general public learned of this massive data gathering effort.

The EFF has published a “Score card” with seven criteria one must consider when using these apps. The details of which are here:

In it, most commercial and open source apps are featured and given a score based on these principles:

Is data encrypted in transit?

Is data encrypted so the provider can’t read it?

Can you verify contact’s identities?

Are past communications secure if your keys are stolen?

Is the code open to independent review?

Is security design properly documented?

Has there been any recent code audit?

Every app known by EFF gets one point for each of the above principles. About nine of these apps have a perfect score. They are:

ChatSecure and Orbot


Pidgin - Off the record messaging for Windows

Signal and RedPhone - Android and iPhone

Silent Phone

Silent Text

Telegram Secret Chats


Though all of the above apps have a perfect scorecard, in this article, I will also write about the ones that don’t have perfect scores, and why you can still use them, under specific conditions.

Lets go back through the years and examine some of the apps that were available in the Pre_Snowden years, and review why you should not use them. Let's begin with the most popular application, Skype.


A long time ago, Skype was released to the world in 2003 by Niklas Zennstrom from Sweden and Janus Friis from Denmark. The software was created by Estonians Ahti Heinla and others. Public Beta copies were released on Aug 29, 2003. Skype supports conference calls, video chats and text chats. Calls are encrypted end-to-end initially, but that changed when Microsoft acquired it.

Skype was one of the first multi-platform VOIP and video call apps that worked on both Windows and Mac platforms. It was originally released for the Windows platform. The initial Mac release was quite buggy and unstable, but it was free. Skype started out quite small, but eventually became one of the most popular VIOP apps for free voice and video calls. Its biggest problem is that it is not Open Source, and instead us a proprietary model. In September of 2005, Skype was sold to eBay for $2.6 Billion. Skype also bridged the gap between normal telephone calls and VOIP. It was possible (provided you paid for it) to make calls from Skype to normal phone lines. Their international rates to land line phones are approximately 2 cents a minute, and domestic phone calls are flat rate, provided you pay a small yearly fee. Calls to Mobile phones are more expensive, and due to tariffs, can cost up to 30 cents a minute. As of late, they are less expensive, averaging around 10 cents a minute to mobile phones.

In May of 2011, before Skype was bought out by Microsoft, it was a peer-to-peer system, however since May of 2012, it is entirely powered by Microsoft “Power Nodes”. Before the Microsoft acquisition, on May 27th, 2011, Skype experienced a major outage that hit the internet community worldwide, regardless of the platform you used. It was believed that the cause was due to a major Microsoft upgrade where Microsoft's systems were overloaded. Shortly thereafter, Skype’s distributed systems were hammered and overloaded as well, and eventually everything was shut down.

It is alleged that just after Skype was hammered due to the outage, the NSA approached them, and pressured them to allow the NSA to read Skype texts and listen in on conversations. Again, this is not verified, but rumors do exist among the security community.

All Skype users were forced to download a new version, and the older versions were disabled. Obviously, NSA involvement is conjecture, but the timing appears to be spot on. A year later, Microsoft acquired Skype, and from May 2011 to present, Skype can not be trusted for secure computer to computer chats, voice or Video.

SIP applications

There are obviously a lot more VOIP apps out there, and once the SIP (Session Initiation Protocol) became in common use, a number of other applications were released. However, the implementations for the Mac lagged behind. Most of the Apps available were proprietary, and some took the liberty to diverge from the normal SIP protocol. An example would be X-Lite, which was not written as a native app, so it had a lot of “Baggage” and hogged resources on the Mac. There is still a lack of good SIP compatible apps out there, and the SIP servers used by these apps do not completely comply with the official SIP standards.

With the release of the iPhone and other smart phones, it didn’t take long for Skype to support them. Once people realized how aggressively the NSA works to “own” your conversations, and tap into your life, it didn’t take long for other applications to start appearing.

I’m listing these apps in order of my own personal discovery of them, starting with my first experience using secure apps.


I was first introduced to Wickr in 2012. I had a very early OS on my iPhone, so newer apps wouldn’t run. Since Wickr runs on the earlier versions of IOS, it’s the one I recommend as long as you just want to use text communications. I do not find this limiting because IMHO most people seem to prefer texting rather then using full duplex telephony, which Wickr doesn’t support. According to recent reports, Wickr has a score of 5 out of 7, but according to my conversations with them, I think this might change. EFF states that Wickr is not open to independent review, and the security design is not properly documented, but they did send me this URL, which might address these two issues.

The above white paper has no publication date, but I suspect this is pretty recent.

Wickr deploys end-to-end encryption, and until the message is read by the recipient, the message stays encrypted. Wickr cannot read it even when requested by law enforcement. Therefore Wickr is a good choice for privacy. Your Wickr password is not recoverable. However, if you lose your device and happen to remember your password, the entire profile can be restored to your new device. Which means messages can be decrypted now on both devices. There is a method to verify if your messages exist on two devices (if you trust Wickr servers), but this scenario points to keys actually being stored at the server level regardless of what the the documentation states.

Wickr was founded in 2012 by a group of security experts and privacy advocates. Nico Sell was the CEO until May 2015, when she became the co-chairman of the Wickr Foundation.

One of the best features of Wickr is the ability for it to set an expiration date of encrypted messages decrypted locally on your phone. So if your phone falls in the wrong hands, all your decrypted messages are deleted within a specified time, specified in individual message settings.

Wickr generates a new key for each message you send, so no one can decipher messages except the recipient, not even Wickr or the NSA.

As of December 1st 2015, Wickr has passed a recent independent security audit. This shouldraise their score to 6, assuming EFF’s final review.

Wickr employs the Industry standard AES256 Encryption protocol to secure your data. Another Scrambler is deployed to protect header parameters, between the App and the servers, so not even MetaData can be extracted. This is due to the multiple layers of encryption, making it one of the best (and most prolific) apps out there. Wickr not only runs on Android and iPhone, but it also runs on laptops, desktops, Linux (Ubuntu, I think), as well as Microsoft and Apple OS.