Rangzen / Murmur

Murmur (formerly Rangzen) is live!

De Novo Group is excited to announce the launch of Murmur (formerly Rangzen)!

Murmur is a free, open-source, anonymous messaging Android app that does not require an Internet connection. Messages are not sent in real-time like with other messaging apps that rely on the Internet and have a central server, but instead spread directly from one device to another (forming a delay-tolerant peer-to-peer network) without user intervention using Bluetooth and WiFi Direct. The more devices the faster the message spreads and if no device is around, the message is queued in the feed to be sent later. Users control their anonymity and decide what information to share. Lastly, Connection Scores help users filter spam messages and Restricted Messages limit the audience to their friends.

The motivation for the project originated in the days of the Arab Spring when a need to help citizens of oppressive regimes circumvent government-imposed communication blackouts was identified . Our implementation followed the tenets laid down in the UC Berkeley EECS research paper called “Rangzen: Circumventing Government-Imposed Communication Blackouts”:
- Infrastructure Independent: A mobile mesh that easily scales without compromising users’ safety
- Trustworthy: Leveraging social connections to resist attack and infiltration
- Private: Providing strong anonymity guarantees to users to preserve their privacy

Download Murmur on the Google play store:


Murmur is a free anonymous messaging app that does not require an Internet connection! You can use Murmur to:* Post public, restricted or self-destruct messages to the network* Use the feed to sort, search, save and delete messages* Endorse messages you like* Control your anonymity by deciding what information to share* Filter trustworthy messages using a Connection Score assigned to each message Key facts about Murmur:* Open-source - the source code is available on GitHub and we welcome your fe...


The project is hosted on the public Git repo at:

We welcome your feedback and involvement and want to deeply thank all of the core team and everyone that has helped us along the way.

Project Rangzen was supported by a $1,500,000 grant from the US department of state, the Bureau of Democracy, Human Rights, and Labor, under the Internet Freedom program.

More background information about the project:

The solutions we develop will enable free communication, independent of government or corporate-controlled infrastructure, while providing strong anonymity guarantees.
To better understand the challenge and our approach – here’s a short introduction.
At the core of this work, is our recent study – Rangzen, on which we’ll build the remaining elements for a widely deployable solution. Some of these elements pose fascinating research challenges, while others call for skillful integration of existing solutions.

Our work is freely available as open-source encouraging peer review and transparency.

We work in tight collaboration with the TIER group and the Data and Democracy Initiative (DDI).

  • Rangzen is the Tibetan word for Freedom/Liberty/Independence.

Rangzen Reports and Publications

The idea at the core of the Rangzen project:
Giulia Fanti, Yahel Ben-David, Sebastian Benthall, Eric Brewer and Scott Shenker

Discussion of the constrains in the design of Dissent Networks:
Shaddi Hasan, Yahel Ben-David, Giulia Fanti, Eric Brewer and Scott Shenker. (direct link - .pdf)