Disclaimer : All the experiments to be done on your risk. This article is for education purpose. I am not responsible for any bricked or damaged devices! Also note that you must be rooted in order for the Custom Recovery installation to work!
What is a Custom Recovery?
Before I tell you what a custom recovery is it might be a good idea for you to know what a recovery is in general at least pertaining to computers. In Windows Microsoft has included a recovery system inside of the operating system. On Windows once your in the recovery you can do a factory reset, reinstall windows, and more. The stock recovery that comes with an Android is similar to that of a Windows machine, but it’s a little bit different. In a stock Android recovery you can do a factory reset, wipe cache, wipe dalvik cache. Cache is just temporary data that is stored on your device. You can also Install updates from ADB (Android Debug Bridge, we will get into that some other time) and install updates from SD. When you install updates from SD that could be either you internal storage on your device or an actual SD card. What is the difference between a stock recovery and a custom recovery you ask? Well the difference is with a stock recovery you are only able to flash (install) updates or ROM zip files that have been digitally signed by the manufacturer of you device, but with a custom recovery you can flash whatever ROM or extra goodies that you want. Just be sure it’s compatible with your device. Installing a custom recovery is the key to installing a custom ROM. Remember that!
Why Install a Custom Recovery?
Why install a custom recovery? There are many reasons why you would want to have a custom recovery rather then the stock recovery. Like I said a big perk to have a custom recovery is to use it to flash custom ROMs and you need to have a custom recovery to do so. You can also use a custom recovery to flash extra goodies for your custom ROM. For those of you who are on Android 5.0 and up, and want to install the Xposed Framework and Modules you need a custom recovery to actually install the Xposed Framework onto your device. Another big reason why it is very helpful to have a custom recovery is because you can do Nandroid backups. Nandroid backups are FULL backups of your whole entire system. All your apps, app data, settings, wallpaper, and everything else that you have on your device, and you can restore it anytime you want as long as you can enter the recovery. So if something goes wrong during a ROM installation you can restore your backup of the previous ROM.
How to Install a Custom Recovery
What good is knowing about all this stuff about a custom recovery if you don’t know how to install it. Well that’s where I’m here to help. There are a fair amount of custom recoveries out there, but the two most popular, and supported recoveries out there is Clockworkmod and TWRP (Team Win Recovery Project). Although support and popularity for Clockworkmod is slowly going away. In terms of how you get around the recovery Clockworkmod is very similar to the stock recovery. It looks pretty similar. You can use the volume keys to move up and down and the power button to select, or you can use the touchscreen to select. Although out of experience both ways are kind of cumbersome. TWRP is a lot different than Clockworkmod in terms of design and UI. There are different boxes you can tap on the screen to get where you need to go. It’s less cumbersome then Clockworkmod. For a first time modder TWRP will definitely be easier to use. Also TWRP is slowly overtaking Clockworkmod, and I suspect that in a few years Clockworkmod will be gone, but enough of me ranting about which recovery is better. Let me tell you how to get a custom recovery on your Android device. One way to get either TWRP or Clockworkmod is to download the ROM Manager app from the Play Store. Once you open the app it will prompt you to pick which recovery to install between either TWRP of Clockworkmod. You can also download the official TWRP Manager app from the play store to get the TWRP recovery, and the TWRP app will do the install for you. Please note that not all devices are compatible with TWRP or Clockworkmod.