So you are a flashaholic and like to try different roms on your Android device. In case you own a HTC One you can now do so by using Multirom. As of now only the international HTC One is supported but if you have a AT&T or T-Mobile HTC One it should work but try at your own risk.
MultiROM is one-of-a-kind multi-boot mod for HTC One (international). It can boot any Android ROM as well as other systems like Ubuntu Touch, once they are ported to that device. Besides booting from device’s internal memory, MultiROM can boot from USB drive connected to the device via OTG cable. The main part of MultiROM is a boot manager, which appears every time your device starts and lets you choose ROM to boot. You can see how it looks on the left image below and in gallery. ROMs are installed and managed via modified TWRP recovery. You can use standard ZIP files to install secondary Android ROMs and MultiROM even has its own installer system, which can be used to ship other Linux-based systems.
* Multiboot any number of Android ROMs
* Restore nandroid backup as secondary ROM
* Boot from USB drive attached via OTG cable
For installation the HTC One must not be encrypted, installation is a 3 step process and your current rom will not be erased.
- Flash Multirom in recovery
- Flash modified TWRP from fastboot or use flashify
- Flash patched kernel in recovery
Download links for all the files mentioned above can be found here. Once done to flash another rom go to recover, select Advanced -> MultiROM -> Add ROM. Select the new ROM’s zip file and confirm to flash.
To update primary rom.
- Flash ROM’s ZIP file as usual, do factory reset if needed (it won’t erase secondary ROMs)
- Go to Advanced -> MultiROM in recovery and do “inject current boot sector”
To update/delete/add other roms.
- Go to Advanced -> MultiROM -> List ROMs and select the ROM you want to update.
- Select “Flash ZIP” and flash ROM’s ZIP file.
As always have a nandroid in case you have any issues and proceed at your own risk.