[BLU R1 HD Guides, News, & Discussion] James.ptrsn:
I've seen a lot of questions about the unlock/root possibilities with new Blu R1 HD and I thought I'd post my experience with the phone last week / post a guide to follow what I did.

My wife's phone broke and had to be sent in to the manufacturer for repairs which could take up to two weeks after they receive it. I have a Blu R1 HD I bought in August last year that I installed the non-Prime OS on and thought that might be a good way to go, so we decided to get a Blu R1 HD and FreedomPop service to give her something to use in the meantime (her phone was a Nexus 5X on google fi so we couldn't just put her current SIM in it). I was a little concerned at first about whether or not it could be unlocked and converted to a non-Prime version but decided to give it a try anyway.

Fortunately, the phone I received was version 7.4 .2. From what I have gathered, if your version is any higher than 7.4.2 you can't do anything. Along those lines I did made sure to not let it update and did the minimum required to get to where I could enable developer settings / ADB, etc.

The end goal was to install the non-Prime OS. In order to do that, you have to have the preloader that can use SPFT so rolling back the preloader was where I started.

The directions for rolling back the preloader are at: https://xdaforums.com/r1-hd/how-to/r1hd-update-6-6-bootloader-roll-t3491096

In order for the roll-back procedure to work you have to have the bootloader unlocked and a custom recovery installed, so it's off to another page for that (the link is on the preloader rollback page as well): https://xdaforums.com/r1-hd/how-to/unlock-tool-t3561333

The instructions are pretty clear and the tool is great, so I just followed the steps listed to bootloader unlock and install TWRP.

With the bootloader unlocked and TWRP installed you are ready to roll back the preloader. Once again, the tool provided is great so just follow the directions. I will say though that both this and the previous tool require some input on occasion for when the phone is in a particular state, so mind your stray key-presses. If you mess up, just start over.

Now that the pre-loader is rolled back you can flash the non-Prime OS. The directions can be found at: https://xdaforums.com/r1-hd/how-to/guide-convert-to-prime-rollback-ota-t3432499

This requires you to download some tools and will directly overwrite the flash to the non-Prime OS. Don't worry that it says you can't use it past 7.4.2; with the preloader rolled back it'll just overwrite the flash directly so the OS version you have installed doesn't matter.

Ironically, now that you've flashed the non-Prime OS you've lost the unlocked bootloader and TWRP because those sectors of the flash were overwritten. Luckily, the process for bootloader unlocking and installing TWRP is much easier on this OS. The instructions for this are at the same post as the one for flashing the non-Prime OS. Basically you just boot to fastboot, OEM unlock, and flash the recovery. You can root here too, if you'd like by following the included directions on the same post.

At this point I decided to do a little bit of debloating. These scripts are installed from recovery and instructions and files can be found here: https://xdaforums.com/r1-hd/how-to/guide-ad-removal-debloat-block-ota-easy-t3429555

The whole process itself didn't take that long, but it did take a lot of searching and some courage to figure out and try the steps needed to do this.

I would also recommend making nandroid backups along the way and even make a system dump using SPFT before flashing the non-Prime OS. Instructions can be found here under "Dump Full ROM": https://xdaforums.com/showthread.php?t=2540400

The next steps are to try to figure out what the most up-to-date version of the non-Prime OS is that I can safely install and to figure out how to do that. If anyone can point me in the right direction, that would be appreciated.

TLDR;

On 7.4.2:

https://xdaforums.com/r1-hd/how-to/r1hd-update-6-6-bootloader-roll-t3491096:

Roll back preloader:​

https://xdaforums.com/r1-hd/how-to/unlock-tool-t3561333​

Unlock​

Install TWRP​

Roll back preloader​

https://xdaforums.com/r1-hd/how-to/guide-convert-to-prime-rollback-ota-t3432499

Install non-Prime OS:​

Unlock​

Install TWRP​

Root​

https://xdaforums.com/r1-hd/how-to/guide-ad-removal-debloat-block-ota-easy-t3429555

Debloat​

I'm not a developer and can't answer any difficult questions/problems you may have along the way but I'll help if I can.