[Nexus 5 Android Development] StrifeSoldierVII:
Dual Boot Custom ROM With Android L Preview

Why would you want to use MultiBoot with the Android L preview

?

Because this is only a preview release and probably should not be your daily driver. By dual booting, you can still have your normal daily driver ROM as well as being able to test Android L on the side whenever you want without having to sacrifice anything, be it data or time. It's just a more convenient and efficient way to go about the situation, in my opinion.

How to dual boot a custom ROM with the new Android L preview

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You'll want to go to the Play Store on your main ROM and download this app: https://play.google.com/store/apps/details?id=com.tassadar.multirommgr&hl=en

1. Open the MultiROM Manager app and under "Install/Update" make sure "MultiROM v26" and the recovery are both checked (recovery is required anyways.) If you already have a custom kernel of your choosing installed I would leave the kernel alone, otherwise go ahead and check the kernel box and choose the appropriate version you are running.

2. Next, tap "Install" and then let it download and reboot. Then, make sure you have the Android L preview Stock ROM zip from this thread downloaded. Put it somewhere on your phone internal storage... let's say the "Download" folder. Reboot into the new MultiROM TWRP recovery, tap "Advanced", tap "MultiROM" (bottom right), tap "Add ROM", (top right), keep ROM type set to Android, don't share kernel, install to internal memory (only one option anyways), tap "Next", choose "ZIP file" for the ROM source, navigate to the Android L preview zip you downloaded from this thread (I chose the "Download" folder), select it and then swipe to confirm.

3. Let it finish installing, and then once you reboot the next time you will be presented with a new MultiROM boot up screen with a short count down timer. Tap the screen to cancel the auto booting of your primary ROM. If all went well you should see two ROM's listed... your main ROM as well as the new Android L preview. Simply tap the Android L preview ROM in the list, hit "Boot" (lower right corner), wait for about 5 to 10 mins for it to boot up for the first time (boot time seems to vary, but it shouldn't be bootlooping though. Just be patient), and then you're all set! It kind of sounds like a lot, but in reality it's pretty quick to do once you've done it a time or two.

How to enable root on the Android L preview ROM using MultiBoot

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Root is not working very well at the moment on L since it's an early preview release and not a final product. Please keep this in mind. Rooting L at this point in time would only be used for testing purposes.

First off, you need to grab the SuperSU zip under the "Main files" part of the thread found here: http://xdaforums.com/google-nexus-5/development/rom-n5-l-developer-preview-t2796003 and put it on your phone internal storage somewhere you will remember. Boot into recovery, tap "Advanced", tap "MultiROM", tap "List ROMs", tap the Android L preview ROM, tap "Flash ZIP", now locate the SuperSU zip you downloaded from the thread and tap it then swipe to install it, and now you're done! Reboot the system back into the Android L preview and you'll have SuperSU installed.

If you have any specific problems related to MultiBoot let me know! I'd be happy to help out when and where I can. Thanks all!