LineageOS

LineageOS is a free and open-source operating system for smartphones and tablet computers, based on the Android mobile platform. It is the successor to the custom ROM CyanogenMod, from which it was forked in December 2016 when Cyanogen Inc. announced it was discontinuing development and shut down the infrastructure behind the project. Since Cyanogen Inc. retained the rights to the Cyanogen name, the project rebranded its fork as LineageOS.

LineageOS was officially launched on December 24, 2016, with the source code available on GitHub. Since that time LineageOS development builds now cover more than 185 phone models with over 1.9 million active installs, having doubled its user base in the month February-March 2017.

Video LineageOS

Background

CyanogenMod (often abbreviated "CM") was a highly popular open-source operating system for smartphones and tablet computers, based on the Android mobile platform. Although only a subset of total CyanogenMod users elected to report their use of the firmware, as of 23 March 2015, some reports indicated over 50 million people running CyanogenMod on their phones. It was also frequently used as a starting point by developers of other ROMs.

In 2013, the founder, Steve Kondik, obtained venture funding under the name Cyanogen Inc. to allow commercialization of the project. In his view, the company did not capitalize on the project's success, and in 2016 he either left, or was forced out as part of a corporate restructure which involved a change of CEO, closure of offices and projects, and cessation of services. The code itself, being both open source and popular, was quickly forked under the new name LineageOS and community efforts began to resume development as a community project.

CyanogenMod offered a number of features and options not available in the official firmware distributed by most mobile device vendors. Features supported by CyanogenMod included native theme support, FLAC audio codec support, a large Access Point Name list, Privacy Guard (per-application permission management application), support for tethering over common interfaces, CPU overclocking and other performance enhancements, root access, soft buttons and other "tablet tweaks", toggles in the notification pull-down (such as Wi-Fi, Bluetooth and GPS), and other interface enhancements. Many of the features from CyanogenMod would later be integrated into the official Android code base. CyanogenMod did not contain spyware or bloatware, according to its developers. CyanogenMod was also said to increase performance and reliability compared with official firmware releases.

Maps LineageOS

Development

Similar to CyanogenMod, the project is developed by numerous device-specific maintainers and uses Gerrit for its code review process. It also retained the old versioning format (for example, Android 7.1 is LineageOS 14.1). Builds are released on a weekly basis and are signed with LineageOS' private keys.

Prior to the official launch of LineageOS, many developers from XDA had already developed unofficial versions of LineageOS from the source code.

On January 22, 2017, the first 14.1 and 13.0 official builds start being rolled out, following the official announcement in a blog post.

On February 11, 2018, the 13.0 builds release have been stopped, while the source code remains available and security fixes are still accepted on gerrit.

On February 26, 2018, the first 15.1 official builds started being rolled out, on select devices, following official announcement in a blog post. The 14.1 versions of Lineage OS will be in active development without feature advancements.

Community

LineageOS allows the community to get involved with the development in various ways. Gerrit is used for the code review process of either the operating system and the infrastructure.

The Wiki, containing information regarding installation, support and development of LineageOS is also open to contributions through Gerrit. Other Lineage platforms include Crowdin for managing translations, Jira for bug tracking, a CVE tracker page for checking out what kernel vulnerabilities have been addressed in a specific kernel (note that this page does not always reflect the real status of the kernel because it has to be updated manually by the maintainer). There is also an official subreddit, r/lineageos, and two IRC channels, hosted on Freenode (#lineageos and #lineageos-dev).

During the month of August, in 2017, LineageOS team held a Summer Survey in which they asked users some feedback to improve the development of the operating system. The results were later published in the month of October, and according to the team, they'll use the gathered data to improve the upcoming LineageOS 15 release.

LineageOS is also known for posting a "regularly irregular review" in their blog in which they expose the work done since the previous post.

Version history

The severe vulnerability of Android (and other) devices to the WiFi KRACK (Key Reinstallation Attack) was addressed in the Lineage ROM as of 16 October 2017. Many devices, which will not receive a patch for the manufacturers' stock ROM, can be protected against KRACK by installing a LineageOS ROM.

Preinstalled apps

LineageOS includes many essential and useful apps, but, like its predecessor CyanogenMod, is free from the bloatware often pre-installed by a phone's manufacturer or carrier.

• AudioFX - Audio optimizer with presets to alter the listening experience.
• Browser - A lightweight browser that relies on the System Webview, for low-end devices, also known as Jelly.
• Calculator - which resembles a four-function calculator and offers some more advanced functions.
• Calendar - Calendar functionality with Day, Week Month, Year or Agenda views.
• Camera - Dependent on device specification will take video or photos, including panoramic. It can also be used to read QR codes. This app is formerly known as Snap.
• Clock - World clock, countdown timer, stopwatch and alarms.
• Contacts - Phonebook for numbers and email addresses.
• Email - Email client that handles POP3, IMAP and Exchange.
• Files - Simple file manager to move, copy and rename files on internal storage or SD card.
• FlipFlap - An app for smart flip covers, only included on select devices.
• Gallery - Organise photos and videos into a timeline or albums for easy viewing.
• Messaging - SMS messaging.
• Music - A music player, formerly known as Eleven.
• Phone - for making calls. Includes speed dial, phone number lookups and call blocking.
• Recorder - A screen and/or sound recorder.
• Trebuchet - A customizable launcher that supports protected apps.

Although they are not included by default due to legal issues, users can flash the normal Google apps, including the Google Play Store and Play Apps with a gapps zip package.

Unique features

LineageOS offers several unique features that AOSP doesn't include. Some of these features are:

• Custom button placement - Set custom location for buttons on the navigation bar, or enable on-screen buttons for devices with hardware buttons.
• System Profiles - Enable or disable common settings based on the selected profile (For example, a "Home" profile and a "Work" profile). The profile can be selected either manually or through the use of a "trigger", such as upon connecting to a specific WiFi access point, connecting to a bluetooth device or tapping an NFC tag.
• Custom Quick-Setting tiles - Quick Setting Tiles such as "Caffeine" preventing the device from sleeping, enabling/disabling Heads Up notifications, "Ambient Display" and "ADB over network" are present to easily toggle frequently accessed settings.
• Expanded Desktop - Force "immersive mode" in apps that don't enable it initially.
• LiveDisplay - Adjust color temperature for the time of day.
• Trust - helps you keep your device secure and protects your privacy.
• Protected Apps - Hide specific apps behind a secure lock. This works hand-in-hand with Trebuchet; the respective app's icon is removed from the launcher, and "secure folders" can be created to easily access these applications. A pattern is used to lock these apps.
• PIN scramble - For users securing their device with a pin, the layout can be scrambled each time the device locks to make it difficult for people to figure out your lock by looking over your shoulder.
• Custom pattern sizes - In addition to Android's 3x3 pattern size, a 4x4, 5x5 or 6x6 size can be used.
• Lock screen customization - The lock screen allows all sorts of customizations, including media cover art, a music visualizer, displaying the weather (if a weather provider is installed), and double-tap to sleep.
• Weather providers - Display the weather in widgets or on the lock screen with a weather provider. This functionality is not included by default; a weather provider must be downloaded from the LineageOS Downloads website.
• Styles - Set a global dark or light theme mode and customize accent colors. This functionality can also be managed automatically by the system based on wallpaper or time of the day (in line with LiveDisplay)

Supported devices

As of 9 February 2018, LineageOS officially builds for 185 devices, including Nexus and Google-released devices. Official builds on the current development branch are labeled as "nightly," although they are generally released once per week with builds for various devices staggered throughout the week to ease the load on the automated build infrastructure. For the first two months of the project, they also produced parallel experimental builds to allow in-place upgrades from previous CyanogenMod installations and ease migration to LineageOS.

Forks

The refusal of support for signature spoofing in official builds for several reasons resulted in the creation of a LineageOS fork with microG services included, known as "LineageOS for microG". The project ships custom builds of LineageOS with the required patch and native F-Droid support, bundled with the MicroG project's free re-implementation of proprietary Gapps. In other respects it follows upstream, shipping OTA updates every seven days. It supports all devices officially supported by LineageOS.

See also

References

External links

• Official website
• GitHub source-code repository
• XDA-Developers - Index thread for unofficial LineageOS releases
• LineageOS Wiki