Spurred by the recent revelations about the US government's PRISM surveillance program, he intends Hemlis Messenger to be an alternative to Apple's iMessage services, WhatsApp and other encrypted messaging services.
The app itself will be free, and paying $5 will unlock its extra features. The whole project is effectively crowd-founded, and the aforementioned fee - payable via PayPal or in Bitcoins - currently goes towards paying for the creation of the app, which will initially be only available for iOS and Android.
According to the service's Twitter account, the half of the funding goal has been reached in one day, so it's reasonable to expect that they will start working on it soon.
The Twitter feed is inundated with questions about the service, but not many have been answered.
Security will be of primary concern, but usability is also a priority. The app will apparently be built on proven technology, such as XMPP with PGP, to make sure it's secure, and central servers will be located somewhere outside the reach of the US government.
Even though many have asked for it to be open source, so that the code can be reviewed by anyone, It is still unknown whether it will be or not, as the project starters haven't yet decided on it.
A few have also asked whether the connection data and relationship data will be hidden, and thus offer plausible deniability for sending / receiving a message. "We will try to achieve that, but can not guarantee it's possible combined with great usability," they replied.
Backers are obviously reassured by Sunde's involvement in the project - it could be said that this project is taking off on the strength of his reputation.
I, for one, am looking forward to seeing how they will go about realizing it.