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Lineage is a very stable, consistent android ROM with many customization options.
SpecsUpdate
Pros
Pro Mostly a stock Android experience
CyanogenMod keeps most of the aesthetic and conventions as they are in stock Lollipop. It uses that as a base to build on top of and add customization options. There's even a Google Apps package that will install the stock apps and Google Now Launcher, but can be avoided if a cleaner experience is preferred.
Pro Provides granular control over personal data
Compared to stock Android, CM12 gives a lot more control over user's privacy. There's a permission manager that can be used to prevent certain apps from accessing certain information, a blacklist for blocking any unwanted calls or messages for specified numbers and notification filter that can be used to remove certain apps from popping up in the notification area.
Pro Customization options
Main strength of CyanogenMod are the customization options that it brings to Lollipop.
For example, status bar items such as clock and battery can be customized, pending notification count can be displayed in the status bar, Quick Settings tiles can be reorganized. It can be set up to adjust brightness by sliding across the status bar or access Quick Settings by pulling down from the edge of the screen. On devices like the OnePlus One there's the ability to switch between onscreen and offscreen navigation buttons. Layout of the onscreen buttons can be changed.
Pro Lots of customization options
The main strength of Lineage OS is the customization options that it brings to Lollipop.
For example, status bar items such as clock and battery can be customized, pending notification count can be displayed in the status bar, Quick Settings tiles can be reorganized. It can be set up to adjust brightness by sliding across the status bar or access Quick Settings by pulling down from the edge of the screen. On devices like the OnePlus One there's the ability to switch between onscreen and offscreen navigation buttons. Layout of the onscreen buttons can be changed.
Pro Built-in weather information
CyanogenMod has built-in weather information accessible from the Quick Settings and powered by Yahoo Weather. From there the weather information can be tapped to access a weekly forecast.
Pro Built-in file browser
CM12 comes with an application for browsing files on the filesystem called File Manager.
Pro System profiles can be triggered based on set criteria
CyanogenMod includes the ability to define profiles that include a set of system settings. For example, a profile for home may include turning on Bluetooth, while a profile for Office could turn down notification volume. They can be switched manually or based on triggers such as location, when on certain Wi-Fi networks or ner a specified NFC tag.
Cons
Con Keyboard vibration
Keyboard typing constant vibration. unable to stop, have deselected in sound settings.
Con Gapps is not included
Unlike most ROM, gapps is not included on this custom ROM.
Con Seems to take forever to boot
Seems to take an awful long to start up on some phones.
Recommendations
Comments
Out of Date Pros + Cons
Pro Powerful theme engine
CyanogenMod theme engine can change almost every aspect of Lollipops design. It evens allows mixing and matching parts of themes. Themes can be found via Cyanogen Themes Showcase or in the Play Store using the keywords "theme engine" and applied simply by installing them as an app and then selecting them in the the 'Themes' section of the Settings menu.