Ultimate Guide to Android Rooting, Custom ROMs & Apps
Android and iOS are the most popular mobile operating systems on the market. Both offer a variety of apps and settings but, eventually reach their limits at a certain point. Rooting or Jailbreaking your phone (or tablet) will offer you thousands of tweaks, skins and new apps that you should not miss out on. It will also help you to remove bloatware.
Quick Links
- Rooting Terms
- How to Root
- Custom Recovery Mode
- Custom ROM versions
- Custom ROMs
- Custom Kernels
- Root Apps
- FAQ
Android Launchers and lock screen widgets are great tools to customize your Android experience without rooting your device. You are also able to root your device and customize it with a launcher and widgets afterwards. If your Android device is rooted but you don’t want flash a custom ROM, Xposed Framework might be the perfect solution for you. You are, however, also able to add new features to your custom ROM with Xposed. With the release of Android 5.0 Lollipop Google replaced the former Dalvik cache with ART. Due to this, Xposed does not work with Android 5.0.
This guide will use the Google Nexus 5 as an example but most of the things also apply to other Android devices. Some might require more work while others can be rooted quite easily, but in the end it’s no rocket science. Rooting and customisation is especially easy on Nexus devices as factory images are freely available on the Google website. However, many other popular devices like the LG G3 can easily be restored using different tools available on XDA developers.
Android Rooting Terms You Should Know
Before we get started, I would like to explain a few terms because the terminology can get complicated and confusing. This will help you to understand other device specific guides. I’ll try to keep it short and not go into (technical) details.
ART
ART stands for Android Runtime and replaces the formerly used Dalvik cache. It was introduced in Android 4.4 and has completely taken over in Android 5.0. I don’t want to go too deep into technical differences, but ART is said to improve battery life and app performance, amongst others.
Bootloader
The Bootloader is your phone’s software foundation. It’s basically what runs before your operating system starts (like a PC’s BIOS). As many manufactures don’t want you to modify your phone’s OS, it needs to be unlocked before you are able to root your phone or install custom ROMs (explained later).
Brick
This is something you don’t want to happen to your Android device. Like the name already implies, a bricked phone (or tablet) can only be used as a paperweight or nice decoration for your apartment. Bricked devices are irreversibly damaged and won’t work anymore. This can, for instance, happen if damaged ROMs are installed or wrong firmwares are flashed. Always make sure to read instructions and verify checksums (a set of numbers that identify the file) to make sure nothing goes wrong. If you’re lucky and your device is only soft-bricked, meaning that it does not boot but still turns on, you might be able to get it back to life.
BusyBox
Android, being based on Linux/Unix, offers a limited amount of UNIX commands (which most users won’t need anyways). BusyBox will implement more commands that are necessary for some root apps to work properly.
Custom ROM
A custom ROM is a modified version of the Android operating system. Tweaks, additional features, different themes or an enhanced performance are usually included. Custom ROMs also offer the possibility to use a newer, unreleased, version of Android on your phone that might usually not be available for your device because of restrictions from manufacturer or providers.
Dalvik
Dalvik is a virtual machine that processes Android app code. Consequently, it is responsible for translating app code into actions on your Android device.
Fastboot
Fastboot is a diagnostic- and engineering tool which offers you several features such as launching in recovery mode or flashing image files.
Kernel
The kernel is the brain of your phone that controls how the system and hardware interact. It’s basically the lowest level of your operating system that manages memory and hardware.
NAND partition
NAND stands for “Negated AND” or “NOT AND” and describes the hard drive partition that stores all system relevant information like the bootloader, recovery mode or the kernel.
NANDroid backup
A NANDroid backup is a complete system backup of your Android device. This backup can be restored later and might save your phone after flashing a faulty ROM or theme.
Radio
The radio is responsible for sending and receiving voice and data. Using an optimized radio can improve your phone’s reception or increase battery life.
Recovery Mode
Recovery mode offers you the possibility to perform system-level tasks (like formatting, defragmenting, etc.), backing-up your devices or install custom ROMs. Android offers a limited stock recovery function. More sophisticated recoveries like ClockworkMod Recovery and TWRP Recovery offer additional features and are easier to use.
Root
Rooting will give you full administrator access of your device. It might also void your warranty (depending on the device and your place of residence), so make sure to handle your device with care after rooting it. You are always able to revert this process by simply flashing a stock-ROM (the original ROM installed by your phone’s manufacturer). Doing this will also “restore” your warranty.
S-OFF
S-OFF means that the NAND partition of your Android device is unlocked. This mostly applies to HTC phones.
Superuser
Rooting your phone will create a new “account” with complete administrative permissions. This superuser account is used by some apps and functions.
Xposed Framework
Xposed Framework is an app that can be installed on a rooted Android device which offers custom ROM like features on stock Android. It currently does not work on devices running Android 5.0 because it requires the Dalvik cache which has been replaced by ART.
How to Fully Backup Your Device Without Root
If your Android device is not rooted yet, you won’t be able to perform NANDroid backups. I wouldn’t suggest to root your tablet or phone without having a proper backup, because there is always a chance of error and you don’t want to brick your device.
Simple ADB Backup let’s you create a full backup of your device without root access and is the perfect solution for users without root access. The free program also offers a restore function and runs on Windows and Linux.
If you’re already rooted, make sure to check out our guide on performing a NANDroid backup.
How to Root Your Android Device
The rooting process differs from device to device which makes it impossible to give general instructions on rooting here. I’ve linked guides for some of the most popular devices below. Using the terms described earlier should make the rooting process easier for you. If your phone or tablet is not on the list, you most certainly can find a guide on the XDA-Developers forums.
Google Nexus 4, Nexus 5, Nexus 7 and Nexus 10
Samsung Galaxy S4
Samsung Galaxy S5
HTC One
LG G2
LG G3
Samsung Galaxy Note 3
Samsung Galaxy S4
Samsung Galaxy S5
HTC One
LG G2
LG G3
Samsung Galaxy Note 3
Always make sure to perform NANDroid backups of your devices to be able to restore your phone or tablet to a working state. I would also recommend to validate checksums and carefully read through the instructions to avoid bricking your device.
Custom Recovery Mode
The standard Android recovery mode is very limited and does not offer many features. That’s where replacement recoveries like Team Win Recovery Project (TWRP) and ClockworkMod Recovery (CWRM) come in place. They offer the possibility to flash custom ROMs which is not possible with the stock recovery mode. Other features include a file browser for update.zips, adb shell and NANDroid backups. Without a custom recovery you won’t be able to flash a custom ROM.
It does not really matter which replacement recovery you install, just go with the one that suits you most. In some rare cases the root script or custom ROM installation only works with either TWRP or CWM. While CWM was pretty much king in the last year, TWRP has taken over and would be my suggestion to go with.
TWRP – Team Win Recovery Project
Team Win Recovery Project‘s custom recovery offers an easy and touch driven user interface. It includes all typical recovery features needed to install custom ROMs, kernels, other tweaks and many more. You are also able to backup and restore your device using TWRP.
CWM – Clockworkmod Recovery
ClockworkMod Recovery is one of the most popular custom recovery modes. It also includes all advanced recovery features like installing custom ROMs and other files, as well as a backup and restore function. You can control the CWM UI via touch or key-input.
Understanding Custom ROM Versions
As Custom ROMs are constantly improved, they usually come in four different categories: Nightly, Milestone, Release Candidate and Stable. This is what you can expect in every stage:
Nightly
Nightly versions are usually generated every 24 hours and can be highly experimental and unstable. Especially early versions of a new custom ROM can have many bugs and missing features. If you want to have the latest features while risking instability – go for nightlies!
Milestone Snapshot
Milestone Snapshots are basically nightly versions that have reached a certain milestone. They can be regarded as being quite stable, but may include certain bugs and issues. Since they are only created every few weeks (or months), they won’t have the latest features that might be included in the nightly versions. If you are looking for the latest features while having a rather stable system, check out milestone snapshots.
Release Candidate
Release candidates, as the name already implies, are one of the last builds before the stable version of a custom ROM is released. RCs are mostly stable but might have a few minor issues. If you’re looking for something stable and ready for daily use, I would recommend to go with release candidates!
Stable
Stable versions are (obviously) the most stable versions around, with all or nearly all problems fixed. Some stable ROMs may still include some smaller issues or certain things not working. Stable versions are definitely the safest way to go, but it might take months before a new stable with new features or fixes is released.
Official, Unofficial & Combined Releases
It is also important to say that custom ROMs are often available as official and unofficial releases. Later use the source code of the official release (if publicly available) and adapt it to devices not supported by the main developers. Unfortunately, this often leads to a delay. In addition to that, many developers combine features of different custom ROMs.