Boot Manager has been used in the past all the time for dual booting your phone, and it let you flash the new ROM to your SD card so that you can try out multiple ROMs in your phone.
How to Use it?
- Download the ROM zip files that you wanted to install to your SD card
- Download and install the Boot Manager(Ensure that you make a nandroid backup of your current ROM before), back up your boot.img and click "Install ROMs" to choose the zip file you have saved. (check all three boxes: Wipe System, Wipe Data, and Wipe Cache.)
- When finished, download the Google Apps zip file for the ROM you just installed and go back to BootManager to install Google Apps' zip file just as the step one. (Leave all three "wipe" boxes unchecked). Also, you can install other add-on zips with this method.
- You can switch between ROMs by going into BootManager and choose "Boot Installed ROM".
Safestrap is a CWM recovery program that allows you to toggle between your stock system and your custom ROM. You can create up to 4 virtual ROM-slots for flashing ROMs.
For the details to use Safetrap, you can refer to detailed Safestrap instructions at droidforums since the process is kind of complex.
Now if you have tried one of the method, you can freely experience different ROMs on your Android phone.
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