meta_title: "The Best Custom Android OSes (aka Custom ROMs) - Privacy Guides"
title: "Alternative Distributions"
description: You can replace the operating system on your Android phone with these secure and privacy-respecting alternatives.
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---
A **custom Android-based operating system** (often known as a **custom ROM**) is a popular way to achieve higher levels of privacy and security on your device. This is in contrast to the "stock" version of Android which comes with your phone from the factory, and is often deeply integrated with Google Play Services.
We recommend installing one of these custom Android operating systems on your device, listed in order of preference, depending on your device's compatibility with these operating systems.
**GrapheneOS** is the best choice when it comes to privacy and security.
GrapheneOS provides additional [security hardening](https://en.wikipedia.org/wiki/Hardening_(computing)) and privacy improvements. It has a [hardened memory allocator](https://github.com/GrapheneOS/hardened_malloc), network and sensor permissions, and various other [security features](https://grapheneos.org/features). GrapheneOS also comes with full firmware updates and signed builds, so verified boot is fully supported.
GrapheneOS supports [sandboxed Google Play](https://grapheneos.org/usage#sandboxed-google-play), which runs [Google Play Services](https://en.wikipedia.org/wiki/Google_Play_Services) fully sandboxed like any other regular app. This means you can take advantage of most Google Play Services, such as [push notifications](https://firebase.google.com/docs/cloud-messaging), while giving you full control over their permissions and access, and while containing them to a specific [work profile](../os/android-overview.md#work-profile) or [user profile](../os/android-overview.md#user-profiles) of your choice.
[Google Pixel phones](../mobile-phones.md#google-pixel) are the only devices that currently meet GrapheneOS's [hardware security requirements](https://grapheneos.org/faq#future-devices).
**DivestOS** is a soft-fork of [LineageOS](https://lineageos.org).
DivestOS inherits many [supported devices](https://divestos.org/index.php?page=devices&base=LineageOS) from LineageOS. It has signed builds, making it possible to have [verified boot](https://source.android.com/security/verifiedboot) on some non-Pixel devices.
DivestOS has automated kernel vulnerability ([CVE](https://en.wikipedia.org/wiki/Common_Vulnerabilities_and_Exposures)) [patching](https://gitlab.com/divested-mobile/cve_checker), fewer proprietary blobs, and a custom [hosts](https://divested.dev/index.php?page=dnsbl) file. Its hardened WebView, [Mulch](https://gitlab.com/divested-mobile/mulch), enables [CFI](https://en.wikipedia.org/wiki/Control-flow_integrity) for all architectures and [network state partitioning](https://developer.mozilla.org/docs/Web/Privacy/State_Partitioning), and receives out-of-band updates.
DivestOS also includes kernel patches from GrapheneOS and enables all available kernel security features via [defconfig hardening](https://github.com/Divested-Mobile/DivestOS-Build/blob/master/Scripts/Common/Functions.sh#L758). All kernels newer than version 3.4 include full page [sanitization](https://lwn.net/Articles/334747) and all ~22 Clang-compiled kernels have [`-ftrivial-auto-var-init=zero`](https://reviews.llvm.org/D54604?id=174471) enabled.
DivestOS implements some system hardening patches originally developed for GrapheneOS. DivestOS 16.0 and higher implements GrapheneOS's [`INTERNET`](https://developer.android.com/training/basics/network-ops/connecting) and SENSORS permission toggle, [hardened memory allocator](https://github.com/GrapheneOS/hardened_malloc), [exec-spawning](https://grapheneos.org/usage#exec-spawning), [JNI](https://en.wikipedia.org/wiki/Java_Native_Interface) [constification](https://en.wikipedia.org/wiki/Const_(computer_programming)), and partial [bionic](https://en.wikipedia.org/wiki/Bionic_(software)) hardening patchsets. 17.1 and higher features GrapheneOS's per-network full [MAC randomization](https://en.wikipedia.org/wiki/MAC_address#Randomization) option, [`ptrace_scope`](https://kernel.org/doc/html/latest/admin-guide/LSM/Yama.html) control, [automatic reboot](https://grapheneos.org/features#auto-reboot), and Wi-Fi/Bluetooth [timeout options](https://grapheneos.org/features#attack-surface-reduction).
DivestOS uses F-Droid as its default app store. We normally [recommend avoiding F-Droid](obtaining-apps.md#f-droid), but doing so on DivestOS isn't viable; the developers update their apps via their own F-Droid repository, [DivestOS Official](https://divestos.org/fdroid/official). We recommend disabling the official F-Droid app and using [F-Droid Basic](https://f-droid.org/en/packages/org.fdroid.basic) **with the DivestOS repository enabled** to keep those components up to date. For other apps, our recommended [methods of obtaining them](obtaining-apps.md) still apply.
DivestOS firmware update [status](https://gitlab.com/divested-mobile/firmware-empty/-/blob/master/STATUS) and quality control varies across the devices it supports. We still recommend GrapheneOS depending on your device's compatibility. For other devices, DivestOS is a good alternative.
Not all of the supported devices have verified boot, and some perform it better than others.
</div>
## Criteria
**Please note we are not affiliated with any of the projects we recommend.** In addition to [our standard criteria](../about/criteria.md), we have developed a clear set of requirements to allow us to provide objective recommendations. We suggest you familiarize yourself with this list before choosing to use a project, and conduct your own research to ensure it's the right choice for you.
- Must be open-source software.
- Must support bootloader locking with custom AVB key support.
- Must receive major Android updates within 0-1 months of release.
- Must receive Android feature updates (minor version) within 0-14 days of release.
- Must receive regular security patches within 0-5 days of release.
- Must **not** be "rooted" out of the box.
- Must **not** enable Google Play Services by default.
- Must **not** require system modification to support Google Play Services.
