The future of our fdroid-compatible app repository

Guardian Project has been running its own fdroid-compatible app repository since 2012. Up until now, we worked to ensure that our repository had the same standards of free software as the official F-Droid repository. Therefore, the Guardian Project repository was included in the official F-Droid client app by default. A lot has changed since then, for the better. F-Droid has long since stopped shipping pre-built binaries from any provider. Back in the day, F-Droid shipped some binaries, like Mozilla’s Firefox APKs, and allowed some non-free libraries in apps. [Read More]

Arti, next-gen Tor on mobile

For software projects with recurring bugs, efficiency or security issues there’s a joke making the rounds in the software industry: “Let’s re-write it in Rust!” It’s a fairly new low-level programming language with the declared goal to help developers avoid entire classes of bugs, security issues and other pitfalls. Re-writing software is very time consuming, so it rarely happens, especially when just one more fix will keep a project up and running. [Read More]

Steps towards trusted VPNs

VPNs have become quite popular in recent years for a number of reasons, and more and more they are being touted as a privacy tool. The question is whether using a VPN does improve privacy. It is clear that VPNs are quite useful for getting access to things on the internet when direct connections are blocked. VPN providers include a number of tactics in both their client apps and server infrastructure to ensure that their users are able to make a connection. [Read More]

Scanning apps, off the record

Smart phones have brought us so many wonderful capabilities. They let people around the world access vast realms of information. They let app developers solve problems large and small in a way most relevent to their local context. They are personal computers for the world. They also have given surveillance capitalism an unprecedented reach into everyone’s lives. Repressive governments use them in ways that the East German Stasi secret police could only have dreamed of. [Read More]

The Search for Ethical Apps: Let's start with governments

Governments across the world are moving services to mobile apps. The vast majority of these apps are only available in the Google Play store or in the Apple App store. Installing apps from these services requires users to agree to their terms of service. This means governments require their citizens to sign opaque and privacy invading contracts with foreign Big Tech in order to use digital services. This feeds ever more into Big Tech data control, filtering, and information bubbles. [Read More]

Implementing TLS Encrypted Client Hello

As part of the DEfO project, we have been working on accelerating the development Encrypted Client Hello (ECH) as standardized by the IETF. ECH is the next step in improving Transport Layer Security (TLS). TLS is one of the basic building blocks of the internet, it is what puts the S in HTTPS. The ECH standard is nearing completion. That is exciting because ECH can encrypt the last plaintext TLS metadata that it is possible to encrypt. [Read More]

New Data Sources: API Key Identifiers and BroadcastReceiver Declarations

A central focus of the Tracking the Trackers project has been to find simple ways to detect whether a given Android APK app file contains code which tracks the user. The ideal scenario is a simple program that can scan the APK and tell a non-technical user whether it contains trackers, but as decades of experience with anti-virus and malware scanners have clearly demonstrated, scanners will always contain a large degree of approximation and guesswork. [Read More]

εxodus ETIP: The Canonical Database for Tracking Trackers

There is a new story to add to the list of horrors of Surveillance Capitalism: the United States’ Military is purchasing tracking and location data from companies that track many millions of people. We believe the best solution starts with making people aware of the problem, with tools like Exodus Privacy. Then they must have real options for stepping out of “big tech”, where tracking dominates. F-Droid provides Android apps that are reviewed for tracking and other “anti-features”, and F-Droid is built into mobile platforms like CalyxOS that are free of proprietary, big tech software. [Read More]

Distribution in Depth: Mirrors as a Source of Resiliency

There are many ways to get the apps and media, even when the Internet is expensive, slow, blocked, or even completely unavailable. Censorshop circumvention tools from ShadowSocks to Pluggable Transports can evade blocks. Sneakernets and nearby connections work without any network connection. Hosting on Content Delivery Networks (CDNs) can make hosting drastically cheaper and faster. One method that is often overlooked these days is repository mirrors. Distribution setups that support mirrors give users the flexibility to find a huge array of solutions for problems when things are not just working. [Read More]

Free Software Tooling for Android Feature Extraction

As part of the Tracking the Trackers project, we are inspecting thousands of Android apps to see what kinds of tracking we can find. We are looking at both the binary APK files as well as the source code. Source code is of course easy to inspect, since it is already a form that is meant to be read and reviewed by people. Android APK binaries are a very different story. [Read More]

"Features" for Finding Trackers

One key component of the Tracking the Trackers project is building a machine learning (ML) tool to aide humans to find tracking in Android apps. One of the most important pieces of developing a machine learning tool is figuring out which “features” should be fed to the machine learning algorithms. In this context, features are constrained data sets derived from the whole data set. In our case, the whole data set is terabytes of APKs. [Read More]

Tracking the Trackers: using machine learning to aid ethical decisions

F-Droid is a free software community app store that has been working since 2010 to make all forms of tracking and advertising visible to users. It has become the trusted name for privacy in Android, and app developers who sell based on privacy make the extra effort to get their apps included in the F-Droid.org collection. These include Nextcloud, Tor Browser, TAZ.de, and Tutanota. Auditing apps for tracking is labor intensive and error prone, yet ever more in demand. [Read More]

NetCipher + Conscrypt for the best possible TLS

A new NetCipher library has recently been merged: netcipher-conscrypt. In the same vein as the other NetCipher libraries, netcipher-conscrypt wraps the Google Conscrypt library, which provides the latest TLS for any app that includes it. netcipher-conscrypt lets apps then disable old TLS versions like TLSv1.0 and TLSv1.1, as well as disable TLS Session Tickets. This is an alpha release because it only works on recent Android versions (8.1 or newer). The actual functionality works well, the hard part remains making sure that it is possible to inject netcipher-conscrypt as the TLS provider on all Android devices and versions. [Read More]

Trusted Update Channels vs. Scratching Your Itch

One of the great things about free software is that people can easily take a functional program or library and customize it as they see fit. Anyone can come along, submit bug fixes or improvements, and they can be easily shared across many people, projects, and organizations. With distribution systems like Python’s pypi, there is an update channel that the trusted maintainers can publish fixes so consumers of the library can easily get updates. [Read More]

IOCipher 64-bit builds

IOCipher v0.5 includes fulil 64-bit support and works with the latest SQLCipher versions. This means that the minimum supported SDK version had to be bumped to android-14, which is still older than what Google Play Services and Android Support libraries require. One important thing to note is that newer SQLCipher versions require an upgrade procedure since they changed how the data is encrypted. Since IOCipher does use a SQLCipher database, and IOCipher virtual disks will have to be upgraded. [Read More]

Tor Project: Orfox Paved the Way for Tor Browser on Android

Last month, we tagged the final release of Orfox, an important milestone for us in our work on Tor. Today, we pushed this final build out to all the Orfox users on Google Play, which forces them to upgrade to the official Tor Browser for Android.. Our goal was never to become the primary developer or maintainer of the “best” tor-enabled web browser app on Android. Instead, we chose to act as a catalyst to get the Tor Project and the Tor Browser development team themselves to take on Android development, and upstream our work into the primary codebase. [Read More]

NetCipher update: global, SOCKS, and TLSv1.2

NetCipher has been relatively quiet in recent years, because it kept on working, doing it was doing. Now, we have had some recent discoveries about the guts of Android that mean NetCipher is a lot easier to use on recent Android versions. On top of that, TLSv1.2 now reigns supreme and is basically everywhere, so it is time to turn TLSv1.0 and TLSv1.1 entirely off. A single method to enable proxying for the whole app As of Android 8. [Read More]

PanicKit 1.0: built-in panic button and full app wipes

Panic Kit is 1.0! After over three years of use, it is time to call this stable and ready for widespread use. Built-in panic button This round of work includes a new prototype for embedding PanicKit directly into Android. Android 9.0 Pie introduced a new “lockdown” mode which follows some of the patterns laid out by PanicKit. [Read More]

Exploring possibilities of Pluggable Transports on Android

Pluggable Transports (PT) give software developers the means to establishing reliable connections in DPI-filtered network scenarios. A variety of techniques are supported, all available by implementing just one standard. We looked into how this can be put to work in Android Apps. Hence we crafted 3 fully functional PT-enabled prototype Apps based on well known open source projects. All our prototypes rely on obfs4 which is a stable PT implementation widely deployed by Tor. [Read More]

Orbot v16: a whole new look, and easier to use!

Orbot: Tor for Android has a new release (tag and changelog), with a major update to the user experience and interface. This is the 16th major release of Orbot, since it was launched in late 2009. The main screen of the app now looks quite different, with all the major features and functions exposed for easy access. We have also added a new onboarding setup wizard for first time users, that assists with configuring connections to the Tor network for users in places where Tor itself is blocked. [Read More]