A custom ROM is basically a full fledged operating system which uses same kernel used by the vendor in propriety operating system which is in this case are Google and Android but there are differences like in user interface and outer functionality as core remains the same. Custom ROMs are generally free of all the 3rd party apps installed by the vendor and results in much better battery life and fluid performance of the device. Installing a custom ROM requires a device with unlocked bootloader and root access performing which may void device’s warranty and fully wipe the phone, So a backup must be made before installing a custom ROM which can be performed with the help of Nandroid backup. Custom ROMs results in frequent updates and fast bug fixes as developer is not bind by any policies as in case of proprietor vendor. Some of the most popular Custom ROMs for Android are listed below:
Probably the most popular custom ROM out there with support of almost all the major android devices. It is the oldest player in the market of custom ROMs. It also provides a custom installer which will install CyanogenMod on your phone. It was featured on Google Play store for some days before Google took it down. There are nightly, snapshot and stable builds available for each device out of which nightly is first build of the OS and snapshot is nearly bugfree version of the ROM and stable being the final build. The latest build is CM11 based on stock android kitKat 4.4 which is still in nightly phase and almost all the devices are supported by nightly builds. It is also turning itself into a standalone OS as a rival to Android.
Paranoid Android provides almost all the similar features and customizations as CyanogenMod. Thjs is the forst ROM to be based on Jellybean 4.2.2 and provides some unique UI customizations like setting the DPI according to the application, changing color scheme in the settings panel, different interfaces for tablet, phablet and phone and multi-window feature which is still in beta phase.
AOKP is acronym for Android Open Kang Project. It is a very simple ROM and all the tweaks are present in ROM control menu. Most of the Motorola, HTC and Samsung devices are supported by this ROM. It is not as stable as CyanogenMod but is much fast and fluid in usage. Features like customizable LED, custom toggles, vibration patterns and Ribbon makes this ROM different from others.
Slim ROMs as the name suggest is a slimmer version of stock Android and features a minimalistic design but that doesn’t compromises with the functionality that this ROM offers and is available for almost all the popular devices by different carriers. SlimROMs are updated weekly hence users can expect frequent updates, bug fixes and healthy improvements.
Liqud Smooth is a very fast, fluid and stable custom package loaded with features like SlimPie, Hardware key rebinding, Custom Carrier label and Liquid Dungeon and many more. Liquid Smooth backup app is also available on Google Play Store and can be downloaded from here.