How to Install MultiROM on the OnePlus 3 and OnePlus 3T

For those who like to try out different custom ROMs at the same time, you can follow these steps to install MultiROM on both the OnePlus 3 and OnePlus 3T.

The OnePlus 3 and the OnePlus 3T are both incredibly popular devices among the developer community right now. This results in multiple custom ROMs that us enthusiasts can choose from. Each custom ROM has its own set of features and unique look to it and having that much choice is always great to have.

The trouble about this is that it can result in spending a lot of time creating Nandroid backups, flashing a new ROM, and then restoring the backup if you didn’t like it.

There are other use cases for MultiROM, naturally, but having MultiROM installed gives us the ability to have two ‘slots’ so to speak on our devices. We can install one custom ROM (which can even just be regular OxygenOS) in one slot and then install a secondary custom ROM in the second slot. So when you boot the OnePlus 3 or OnePlus 3T, you can choose which slot you want to boot from. So today I want to walk you through how to install MultiROM on the OnePlus 3.

Before you begin though, you need to have some things setup ahead of time. For instance, you need to unlock the bootloader of the OnePlus 3 or OnePlus 3T. You then need to install TWRP on the OnePlus 3 or the OnePlus 3T. Lastly, you need to disable forced encryption on the OnePlus 3 or OnePlus 3T. When that is done, you can proceed with the guide below. It’s also a good idea to create a recent Nandroid backup of the OnePlus 3 or OnePlus 3T in case you want to do a restore in the future.

Installing MultiROM on the OnePlus 3

1. Download the MultiROM Uninstaller (OnePlus 3 – OnePlus 3T)
2. Download the MultiROM Installer .ZIP (OnePlus 3 – OnePlus 3T)
3. Download the modified version of TWRP (OnePlus 3 – OnePlus 3T)
4. Boot the OnePlus 3 into Recovery Mode
5. Tap on the Install button
6. Tap on the Install Image button
7. Browse to and tap on the modified TWRP .IMG file
8. Tap on the Recovery option
9. Swipe the white arrows to the right to install it
10. Tap the Home button
11. Tap the Reboot button
12. Tap the Recovery option and wait until you’re booted back into TWRP
13. Tap on the Install button again
14. Browse to and tap on the MultiROM Installer .ZIP file
15. Swipe the white arrows to the right to install it
16. Tap the Home button
17. Tap the MultiROM main menu button at the top right
18. Tap on the Settings option
19. Make sure the enable No-KEXEC Workaround enabled
20. Tap the Home button
21. Tap the Reboot button
22. Tap the System button

Explanation

At this time, I don’t have much experiencing with MultiROM itself. Most of it is straight forward once you understand what the mod actually does (with allowing you to boot into one of two installed custom ROMs). So I may do a series of videos in the future that dive into MultiROM much deeper. This one is only about installing it and as you can see the process is rather straight forward. There are a number of steps you need to take, and you do have to download specific versions of files.

But overall, it’s entirely straight forward. So once you have the Uninstaller, Installer and modified version of TWRP one the OnePlus 3, you can then boot the device into Recovery Mode (which should be TWRP). From here, we need to tap on the Install button, and then the Install Image button (toward the bottom right) because we need to install the modified version of TWRP. So browse to and tap on that image file and then make sure you’re installing it into the Recovery partition.

Swipe the white arrows to the right to begin the installation and it should be finished in a few seconds. We then need to tap on the Home button, then tap on the Reboot button, and then tap on the Recovery button because we need to boot into the newly installed, modified version of TWRP. We won’t be using the modified version of TWRP until we reboot into it after we have installed it. You should see the logo looks different, and we have a new icon at the top right of the TWRP main menu too.

Everything within the regular TWRP menu works as it normally did, so you’ll need to tap on that new icon at the top right of the screen in order to access the MultiROM main menu. We have some special options here that let us manage the current custom ROMs we have installed. Again, there are two slots to install into (primary and secondary), and so when we install, backup, delete a custom ROM we are doing it to one of those specific slots.

This mod can really save you a lot of time if you’re a fan of trying out new ROMs, or simply want to be able to boot into two different versions of the same ROM (which can be useful to have one for work and one for personal use). If you have any questions, I can try to help, but I advise that you check out the XDA thread for MultiROM on the OnePlus 3, or the XDA thread for MultiROM on the OnePlus 3T to get help from people who are more knowledgeable about this mod than I am.