Boot Multiple ROM’s on Nexus 7

The creation of Google and ASUS i.e. Nexus 7 has lived a life of glimmer, it has ruled the 7” tablet market since it’s launch and there is no sign of it slowing down. Since Google launched the 32 GB version and an optional 3G version, the sales have surged ahead previous records. The tablet has a powerful hardware, strong looks and a affordable price, perfect recipe for a successful device. The issue that was faced by most was lack of memory, but that was quickly resolved as you can use your flash drive to connect with Nexus 7, and as days went ahead, the few rough edges were refined by developers at XDA, the latest toy to play with is dual boot.

Dual boot refers to the ability of booting more than one operating system on your device. Consider this example, if you are running windows 7 on your computer and install windows 8 on a different partition you will have two OS installed on your device, and, you could boot into either. Same goes the case with Nexus 7; while it might seem tempting, novice users are not adviced to take a chance with it.

The procedure is dangerous, you will be messing with the boot sector and might brick your device. HardwareInsight takes no responsibility of any such event.

Installation

It is going to be a two part installation, first the multioot hack, then then the modified recovery to manage multiple ROM’s.

Step 1: Flash multirom_vX_n7.zip via recovery.

Step 2: Flash modified recovery through fastboot

fastboot flash recovery recovery.img

Adding ROMs

You can add multiple ROM’s from methods given below. Note that your previous ROM installation will NOT be erased.

Android

Go to recovery, select Advanced -> MultiROM -> Add ROM. Select the ROM’s zip file and confirm. As for the space, clean installation of stock 4.2 after first boot (with dalvik cache generated and connected to google account) takes 676mb of space.

Ubuntu

Download Ubuntu image from here (It does not matter which size, I would suggest “rootfs.img for Nexus 7 8GB“, as it is the smallest one). Put the image in the memory of N7 or to USB flash drive and go to recovery. Select Advanced -> MultiROM -> Add ROM and choose “Ubuntu” as ROM type. Then select the Ubuntu’s image and confirm. Clean installation of Ubuntu is 1.5gb big, but it needs 2-3gb for the installation process itself (for the first boot).

Uninstallation

Re-flash boot.img somehow, either get it from your ROM’s installation zip and flash via fastboot or restore from backup. If you want to erase ROMs installed to multirom, erase folder /sdcard/multirom.

Download: MultiROM

Download: Modified TWRP

Download: Installer

Credits: Tasssadar XDA