[Android General] Bnee:
Sorry for posting here, but I was unable to post in Android Development. And I feel this may help people who have trouble installing Nougat 7.1.2 on there Galaxy S4-I337M. As it was quite difficult for me to find the proper tools and method to install this OS.

The instructions are listed below. You will need to have TWRP installed and your phone rooted prior to doing the following

Recommended External SD CARD to save all files required.

Files required

-TWRP-3.1.1- GOOGLE dl.twrp.me/jfltecan/twrp-3.1.1-0-jfltecan.img.tar.html

-Odin3_v3.12.3- GOOGLE odindownloader.com/download/odin3-v3-12-3

-Gapps-GOOGLE opengapps.org/

-Lineage OS 14.1-GOOGLE JFLTE-SIDE-androidfilehost.com/?fid=961840155545596426

*SuperSUGOOGLE download.chainfire.eu/1220/SuperSU/SR5-SuperSU-v2.82-SR5-20171001224502.zip

I would install SuperSu but I believe Lineage has a built in SU. But to be Safe flash it anyways.

That is JFLTE ROM for S4 CANADIAN VARIANT.

Before you do any of this make sure you backup your phone image. This means everything not just apps and user data. If you have older version of twrp; enter recovery and go to backup. Then backup device. Once finished boot device. Save that backup to your PC.

I would recommend you have external SD card as well. Once you have your phone IMG backed up do the following.

Ensure you have Gapps downloaded for 7.1. You can choose which to download. I would recommend Pico 7.1.

It is the one with least google garbage.

Keep all files on phone but SD card is recommended in case of install failures.

Flash twrp 3.1.1 through odin, Make sure it is latest version. Turn off auto reboot on twrp.

When you flash 3.1.1 and odin states it has PASSED. Press VOL DOWN + HOME + POWER.WHEN SCREEN GOES BLANK QUICKLY PRESS VOLUME UP WHILE STILL HOLDING POWER AND HOME. WHEN PHONE SAYS RECOVERY, LET GO OF POWER WHILE PRESSING VOL UP+HOME. This will ensure you enter recovery and not freeze at main. If you cant get into recovery do following.

*Turn off phone. Then power on while holding VOL UP+HOME+POWER.When phone vibrates let go of power and continue pressing VOLUP+HOME. This will ensure your phone boots to recovery. Sometimes the phone will freeze and say SEandroid enforcing and will not allow you to get into recovery. So do the above.

Once phone is in recovery go to wipe. Wipe the following.

DALVIK,

SYSTEM,

DATA,

CACHE.

YOU CAN DO INTERNAL STORAGE, BUT ONLY IF YOU HAVE ALL REQUIRED FILES ON EXTERNAL SD CARD. DO NOT WIPE INTERNAL IF YOU DO NOT HAVE EXTERNAL SD CARD.

!!DO NOT WIPE EXTERNAL SD CARD WHEN DOING WIPE.!!!

Once the wipe is complete Press back to get to TWRP main menu. DO NOT REBOOT AFTER WIPE JUST PRESS BACK KEY.

Then press INSTALL and go to the folder where you saved all the file Lineage rom, Gapps, SuperSU. Your going to go to install the ROM first.

select the folder where its saved and click the lineage os.zip and swipe to flash.

ONCE THE FLASH IS DONE PRESS BACK AND FLASH GAPPS.

THEN PRESS BACK AGAIN AND INSTALL SUPERSU.

ONCE SUPERSU.ZUP IS DONE FLASHING. THEN HIT REBOOT.

!!!******IMPORTANT- WHEN YOU HIT REBOOT YOU WILL SEE OPTIONS STATING INSTALL *NEW TWRP APP* AND SOME OTHER OPTION. YOU NEED TO MAKE SURE THESE ARE **UNCHECKED**. IF LEFT ON YOU WILL GET SEANDROID ERROR. SO MAKE SURE THEY ARE UNCHECKED THEN SWIPE TO REBOOT********!!!

Now your system will boot to lineage. The first boot takes some time, so DO NOT panic. Allow the System to boot up and enter User Setup.

*******DO NOT TURN OFF PHONE JUST WAIT AND THE PHONE WILL LOAD OS AND ENTER USER SETUP***********

Once phone boots into OS. IT will enter Setup and you can take it from there.

Good luck!

PM me for any questions.