What Calyx Institute does

Calyx Institute is a 501(c)(3) non-profit organization based in Brooklyn, United States, founded to educate the public about privacy in digital communications and to develop accessible privacy tools. Its principal product is CalyxOS, a privacy-focused mobile operating system built on the Android Open Source Project (AOSP) and distributed free of charge as an open-source download from calyxos.org. The OS targets privacy-conscious individuals and, secondarily, security researchers and activists, with a horizontal go-to-market delivered entirely through product-led self-service installation via Web Installer or device flashing, supplemented by community engagement on Matrix, Reddit, Mastodon, X, Facebook, Instagram, and an annual FOSDEM presence.

CalyxOS's technical architecture combines AOSP with several integrated privacy components: microG, an open-source re-implementation of Google Play Services with restrictive signature spoofing; the Datura Firewall, a multi-layer (UI, Framework, Connectivity module, Netd) per-app network isolation system using eBPF for traffic monitoring and denial lists; SeedVault for local encrypted backup; Bromite-based Chromium with built-in anti-tracking; F-Droid as the default app store (with a dedicated CalyxOS repository) and Aurora Store as a Google Play alternative; bundled Tor Browser and Tor/Riseup VPNs; randomized advertising IDs; default location-metadata redaction for photos; and randomized MAC addresses for Wi-Fi. The OS supports a locked bootloader for Verified Boot using CalyxOS-owned signing keys. Production builds and OTA updates are signed offline through a hardware security module (HSM) using Shamir's Secret Sharing for distributed key custody, with an append-only audit trail independently audited by Trail of Bits.

The Institute funds CalyxOS development through a 501(c)(3) tax-deductible individual membership program and direct donations; the operating system itself carries no commercial pricing. CalyxOS supports more than 27 devices across four device families — Google Pixel (Pixel 9 series, 8 series, 7 series, 6 series, 9a, Fold, Tablet), Fairphone (4, 5, with 6 upcoming), Motorola (moto g series), and SHIFT (SHIFTphone 8) — and ships monthly security updates generally within the same week as AOSP security bulletins. CalyxOS follows upstream Android versions, with Android 16 test builds released in 2026 after a signing-infrastructure redesign. There are no disclosed funding rounds, enterprise customers, or revenue figures; the company is not venture-backed.

Name

Calyx Institute

Legal name

Calyx Institute

Website

https://calyxos.org

Company type

Private

Founded year

2021

Operating status

Operating

Headcount range

11–50 employees

Short description

Calyx Institute is a 501(c)(3) non-profit that develops CalyxOS, a free, open-source, AOSP-based Android mobile operating system with privacy and security defaults for everyday users and security researchers, funded through memberships and donations.

Ownership category

akta.pro rank

Product category

Privacy-focused Mobile Operating System

NAICS

Software Publishers (5132)

SIC

Services-Computer Integrated Systems Design (7373)

akta.pro primary industry

Identity Orchestration & Policy (Zero Trust Access, Conditional Access) (HDADAAAL)

Keywords

• Privacy mobile OS
• Android mobile operating system
• Open source software
• Mobile security
• Network firewall

Headquarters

HQ city

Brooklyn

HQ country

United States

HQ region

North America

Markets served

GTM type

B2C

Offering type

Software

Cost components

Personnel, Infrastructure, Operations

Revenue model

1. Membership Program: Calyx Institute operates a 501(c)(3) non-profit membership program where individuals pay membership fees to support CalyxOS development. Membership is described as tax-deductible.
2. Donations: Direct donations are accepted through the Calyx Institute website at members.calyxinstitute.org/donate to fund development of CalyxOS.

Go-to-market motion1 record

Distribution channels3 records

Marketing channels6 records

Core offering

Calyx Institute develops CalyxOS, a privacy-focused Android mobile operating system built on AOSP. It ships with privacy-by-default features including microG (a Google Play Services replacement), a built-in Datura Firewall with per-app network isolation, SeedVault local backup, and HSM-signed Verified Boot. The free, open-source OS is distributed directly to end users for self-installation on supported Pixel, Fairphone, Motorola, and SHIFT devices.

Product overview

Calyx Institute offers CalyxOS, a privacy-focused Android mobile operating system built on AOSP. The product portfolio centers on CalyxOS as the core offering, supplemented by microG (an open-source Google Play Services replacement for privacy-conscious users), the Datura Firewall (built-in network isolation and per-app control), and SeedVault (local encrypted backup). CalyxOS ships with F-Droid Basic as its preferred app store and Aurora Store as an alternative Google Play Store client. Development is funded through Calyx Institute's 501(c)(3) non-profit membership program. The OS supports verified boot with locked bootloader and includes monthly security updates following AOSP releases.

Differentiator

Problem solved

Functional benefit

Brands

• CalyxOS: Privacy-focused Android mobile operating system developed by Calyx Institute
• Datura Firewall
• microG
• SeedVault

Products and services

• CalyxOS Privacy-focused Android mobile operating system built on AOSP that puts privacy and security into the hands of everyday users. Supports locked bootloader for tamper protection and provides automatic monthly security updates.
• Datura Firewall Built-in firewall application providing network control at multiple layers (UI, framework, Connectivity module, Netd). Features per-app network isolation, transport type control (Wi-Fi/Mobile Data/VPN), background network restrictions, and eBPF-based traffic monitoring.
• microG (CalyxOS fork) Open-source implementation of Google Play Services that replaces core Google Play Services functionality while maintaining privacy. Supports push notifications, location services, and Google Account login with restrictive signature spoofing.
• SeedVault Local encrypted backup solution for CalyxOS devices that can backup apps and data, including apps that don't normally allow backup. Data remains under user control on device.
• Calyx Institute Membership Program 501(c)(3) non-profit membership program where privacy-conscious individuals pay recurring membership fees to support CalyxOS development. Membership fees are tax-deductible.

Quantifiable outcome

• Monthly security updates released generally within the same week as AOSP security bulletin
• +2 more outcomes

Segments2 records

Ideal customer profiles2 records

Technology focussed Yes

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Integration8 records

Feature9 records

Partnerships

Eight partnerships are on record, tiered core and minor.

• SignalcoreTechnology or IntegrationSignal is recommended as the preferred encrypted communication app in CalyxOS. CalyxOS encourages encrypted communication through Signal integration.
• F-DroidcoreTechnology or IntegrationF-Droid is the preferred and default app store in CalyxOS. Ships with special CalyxOS repository for security updates and necessary app modifications. All apps are free and open source.
• Aurora StorecoreTechnology or IntegrationAurora Store provides an open source alternative to Google Play Store for downloading apps. Includes Aurora Services for privileged updates. CalyxOS maintains a privileged extension.
• Tor ProjectcoreTechnology or IntegrationTor Browser is recommended for anonymous browsing. Free VPN from Tor is included by default in CalyxOS. Tor VPN available from F-Droid.
• microGcoreTechnology or IntegrationmicroG is an open-source re-implementation of Google Play Services. CalyxOS maintains its own fork with restrictive signature spoofing implementation. Required for push notifications and some app functionality.
• BromitecoreTechnology or IntegrationCalyxOS's Chromium browser is based on Bromite, an Android browser with privacy enhancements and built-in anti-tracking filters.
• WeblateminorOthersCalyxOS uses Weblate (hosted.weblate.org) for community-contributed translations of the OS and documentation.
• Trail of BitscoreStrategic or Co-development PartnerTrail of Bits independently audited the HSM-based signing infrastructure and provisioning system for CalyxOS.

Scale indicators2 records

Recent moves6 records

Expansion highlights5 records

Emerging players

• Tails: Tails is a privacy-preserving live operating system booted from USB, focused on anonymity via Tor. While not a mobile OS, it overlaps with CalyxOS in mission (anti-surveillance defaults) and integrates with Tor, one of CalyxOS's bundled default services.
• UBports / Ubuntu Touch: UBports develops Ubuntu Touch, a Linux-based mobile OS for several phones. It targets a similar niche of users seeking an alternative to stock Android/iOS, and competes in community-driven OS development, though with a fundamentally different platform base.

Others

• Signal Foundation: Signal Foundation develops Signal, the default encrypted messaging app integrated into CalyxOS. As an adjacent privacy-mission nonprofit, it is comparable in operating model (501(c)(3), open source, donation-funded, mission-driven) and ecosystem role, though its product is communications rather than an OS.
• Calyx-friendly OEM: Fairphone: Fairphone is a key supported OEM for CalyxOS and an aligned ethical/hardware partner. It is comparable as a privacy-respecting, repairable smartphone maker that ships CalyxOS-compatible hardware, making it an ecosystem peer rather than direct OS competitor.

Direct peers

• Replicant: Replicant is a fully free software Android fork that replaces every proprietary component on the device. Comparable to CalyxOS as an open-source mobile OS alternative for users prioritizing user freedom, though it targets a much smaller set of older devices and a more ideologically-pure use case.
• https://calyxos.org/e/OS: /e/ (Murena) is a de-Googled mobile OS built on LineageOS with microG and privacy-focused default apps, targeting the same privacy-conscious consumer segment as CalyxOS. It competes head-to-head in device support (Fairphone, Pixel, Samsung) and in offering a unified 'non-Google' app ecosystem.
• GrapheneOS: GrapheneOS is the leading privacy- and security-hardened Android-based mobile operating system. Like CalyxOS it targets privacy-conscious users, supports a Pixel-first device matrix, and ships hardening features (verified boot, sandboxed Play Services, network permission toggles). The two are the primary direct comparables in the de-Googled Android category.
• LineageOS: LineageOS is the largest community-driven open-source Android fork. CalyxOS is built on the same AOSP lineage, shares Gerrit-style review workflows, and has explicitly adopted LineageOS components (e.g., Glimpse Gallery). Comparable as open-source mobile OS projects with broad device support, though LineageOS focuses on broader device enablement rather than privacy.
• DivestOS: DivestOS is a hardened Android/AOSP fork focused on security, privacy, and removal of proprietary blobs. It targets a similar power-user / activist audience as CalyxOS and overlaps on supported devices (older Pixels, some FOSS-friendly OEMs) with comparable feature priorities such as verified boot and tracker removal.

Broad incumbents

• Purism: Purism builds privacy-focused hardware (Librem 5 phone) and ships PureOS, a Linux-based mobile OS. It addresses the same 'surveillance-free smartphone' mission as CalyxOS but competes more on hardware/SoC independence than Android compatibility, making it a broader incumbent in the privacy device space.

Market position

Strengths5 records

Weaknesses5 records

Competitive moat4 records

Key risks6 records

Key highlights6 records

Customer concentration

• Xx.com/calyxinstitute
• GitHubgitlab.com/CalyxOS
• Facebookfacebook.com/calyxinstitute
• Instagraminstagram.com/calyxinsta
• LinkedInlinkedin.com/company/the-calyx-institute

Revenue estimate

Valuation estimate

Number of profiles

Profiles1 record

Funding overview

Funding rounds

Investors

Funding detail is available on the Subscription and Enterprise plan.Contact sales →

M&A

Investments

M&A and investment is available on the Subscription and Enterprise plan.Contact sales →

Frequently asked questions about Calyx Institute