After learing a lot from these great devs arround here i decided to start to try out a new project! Multirom!!
You might or might not have heared of it, THE multi-boot mod for the Nexus 7. I found it and have decided to port it for our device.
First of all, it is a very initial release now. Though I have tested multiple cases and didn't find any problem except those in the bug list, bugs can arise. Do have a backup! Also, do read through the whole OP and 2nd post! If you don't understand something, rather read again and/or ask!
For more information on how it works and what it does, I suggest that you read the first few posts in the original thread. Those are very detailed and well-written posts that explain MultiROM in general. Installing roms to USB and Ubuntu/Ubuntu Touch of course doesn't work for our device atm.
The device must not be encrypted!
You need to flash the modified TWRP recovery that has MultiROM extensions. My version is based on the latest sources with gordon0001's device-specific modifications included. You can keep this recovery if you don't want to use MultiROM anymore and you like TWRP, because the MultiROM extensions don't interfere with other functions, even if the boot sector is not injected.
You have to flash a kernel that is capable of Kexec-hardboot.
You can find everything at https://www.androidfilehost.com/?w=files&flid=32204.
multirom-20150521-v32-UNOFFICIAL-p880.zip : The multirom zip
CM12_Kernel_Patched.zip : CM 12 Kernel with Kexec-Hardboot Patch ; Thanks to @Adam77Root the patch and @laufersteppenwolf for building Kernel
multirom_uninstaller.zip : Selfexplaining
-Reboot to recovery doesn't work.
-UI has some graphical bugs
-Double Press to boot Secondary Rom doesnt work -> Press twice on the Rom you want to boot and press Powerbutton at the same time till you recoginze a vibration
-You tell me more
23 May 2015: Initial release
@Tasssadar for MultiROM, Kexec-hardboot for Nexus 7 and his help with debugging and porting
@Adam77Root for Thread Content
[MOD][23 MAY] MultiROM v32, Tool/Utility for the LG Optimus 4X HD
Last Updated 2015-05-24