Replicant is a fully free Android distribution running on several devices, a free software mobile operating system putting the emphasis on freedom and privacy/security. It is based on CyanogenMod and replaces or avoids every proprietary component of the system, such as user-space programs and libraries as well as firmwares.
Replicant aims to be an ethical system: it does not ship nor recommend the use of non-free software.

Many different devices are supported by Replicant, to an extent specific to each device. Basic features such as graphics, sound and telephony (if applicable) are supposed to be working for each device (if not, developers are confident they will work soon).

Replicant is a community-led effort, currently driven by a single developer. Not every piece of software in Replicant should be expected to be fully-featured nor entirely reliable, even though developers are trying their best.

History

Replicant was founded in 2010 as a way to gather initiatives aiming to free the system running on the HTC Dream, the first publicly-available Android device. The project was started by members of LibrePlanet Italia and Software Freedom Conservancy. The first usable version of Replicant was based upon Android 1.5 as released by the Android Open Source Project: after some work, basic functionalities of the HTC Dream were working. Starting from version 2.2, Replicant stopped using AOSP as a base and instead started using CyanogenMod, which contains support for more devices.

Over time, various initial members of the project retired, leaving Denis "GNUtoo" Carikli as the only active developer of the project. However, in April 2011 Paul Kocialkowski, a user of Replicant, started getting involved in development. After porting Replicant to version 2.3 on the Nexus S and later on porting plenty more devices, Paul became the main developer of Replicant and is currently doing most of the work on the project.

Is my device only running free software after I install Replicant?

While Replicant is a fully free system, other components run aside the system, such as bootloaders, firmwares and the modem operating system (if applicable). These components are usually proprietary software. Some devices can also run free software bootloaders: see the documentation specific to each device for more details.
For more information about these issues, read our freedom and privacy/security issues page.

My device is not listed as supported, can I still install Replicant?

Replicant only runs on the listed supported devices. Other devices have to be explicitly ported to Replicant: specific drivers and configurations have to be written so that Replicant can handle the device properly. It is not a good idea to try installing an image for a device that has a similar name: it will fail and may damage the device.
You are welcome to get in touch with us and start evaluating your device as a next target for Replicant!

Is my data safe when stored on a device running Replicant?

While Replicant is a fully free system, some proprietary components that are not part of the system, such as bootloaders, may still be executed (the situation depends on each device). These proprietary pieces have access to the data stored on the device. Hence, they represent a risk for security.
On telephony-enabled devices, if the modem is poorly isolated from the rest of the device, it may also be able to compromise the data stored on the device and apply software changes.
Despite being fully free, Replicant may also be exposed to security issues that were not disclosed and/or fixed yet, like any operating system. Just as well, installing third party applications may bring security issues, especially if they come from untrusted sources. Of course, installing any proprietary application creates a risk for security.

Are my communications safe when using a device running Replicant?

Communications made using the public mobile telephony network should be considered unsafe by nature, as the mobile telephony operator is always able to record and track these communications and is often legally allowed to do so. In addition, it was shown that in some cases, these can be intercepted as a result of the weak encryption in use. Safe communications can be achieved using encryption over the Internet (e.g. through mobile data networks).
However on telephony-enabled devices, if the modem is poorly isolated from the rest of the device, it may be able to access the microphone of the device or access the communications data unencrypted, making any kind of communication unsafe.

Why are some hardware features missing on Replicant?

Most of the time, hardware features are driven by proprietary software in CyanogenMod. While Replicant is fully free, these proprietary parts are either replaced or avoided in Replicant. Such parts being avoided instead of replaced is the result of missing free software support for that hardware. It happens because developers failed to write free software support for that hardware, as a result of incomplete or missing documentation from the manufacturer, lack of time to perform reverse engineering or generally speaking, lack of proper resources.
Keep in mind that writing free software replacements is a technically complex task that does not always succeed, especially when the manufacturer doesn't communicate how to use the hardware.

How exactly is Replicant different from CyanogenMod?

Replicant uses CyanogenMod's source code as a base. It is rebranded to provide the Replicant look and feel (wallpapers, logos) and parts of the code are reworked to remove anti-features that can spy on the user. Most importantly, Replicant does not include any of CyanogenMod's proprietary components (programs, libraries, firmwares) and instead provides free software replacements for some of these. The rest of the system is also adapted so that the free software replacements can run correctly.

Why is Replicant based on CyanogenMod instead of OmniROM?

Replicant is currently based on CyanogenMod for historic reasons: it was started before OmniROM and the current version of Replicant is not supported by OmniROM, so CyanogenMod is currently the only choice that makes sense. Furthermore, CyanogenMod supports more devices than OmniROM, which makes porting a new device to Replicant easier. On top of that, some devices that are currently supported by Replicant are not in OmniROM. However, we are aware that OmniROM's general position is more friendly towards free software (even though it still ships with proprietary software): we will seriously consider OmniROM as a base for the next major version of Replicant.

Why doesn't Replicant ship with proprietary components when free replacements are missing?

Replicant is a free software project and thus does not encourage nor enforce the use of proprietary software. Shipping proprietary software is a way of taking the decision for the user to use proprietary software, which is not an ethical nor respectful thing to do.

Why doesn't Replicant guide users through installing complementary proprietary components?

Replicant is a free software project and thus does not encourage nor enforce the use of proprietary software. Providing instructions to install such components is a way of encouraging the use of proprietary software, which is not an ethical thing to do.