MultiROM is a one-of-a-kind multi-boot solution. It can boot android ROM while keeping the one in internal memory intact or boot Ubuntu without formating the whole device. MultiROM can boot either from internal memory of the device or from USB flash drive.
XDA threads:
- grouper: http://forum.xda-developers.com/showthread.php?t=2011403
- flo: http://forum.xda-developers.com/showthread.php?t=2457063
###Build
Clone repo to folder system/extras/multirom inside Android 4.x source tree.
MultiROM also needs libbootimg (https://github.com/Tasssadar/libbootimg)
in folder system/extras/libbootimg. Use something like this to build:
. build/envsetup.h
lunch full_grouper-userdebug
make -j4 multirom trampoline
To build installation ZIP file, use multirom_zip target:
make -j4 multirom_zip