[Samsung Galaxy S7 Edge Guides, News, & Discussion] lugnut2099:
So I'll kick things off with a bit of root discussion/issues...

I rooted my phone maybe a week or so after getting it back in July, taking the chance against my better instincts that the instructions found over in this Verizon thread would work out for USCC phones too. Much to my surprise, not only did it work, I experienced almost none of the many problems that the Verizon users kept encountering in the early weeks of that thread. Why that is, though, I still have no clue. I guess VZW's software is somehow different from USCC's in such a way that we simply weren't affected by whatever kept causing the boot loops, extreme battery-drainage and heat issues for those phones. (Mostly...)

I don't want to steal the work of thread-starter psouza4 or anyone else in that existing Verizon thread so I don't want to try and rewrite every full detail but for any future USCC S7/Edge owners who might wind up here, I guess I'll do a real basic rundown of exactly how I did mine (and also I'll do it so that maybe someone more versed in Android-tinkering than me can tell me where I may have gone wrong on certain steps). The files I used in my root/fix/debloat process are the ones listed in Bold below and all can be found on that thread - I'd link 'em directly here but I don't know how kosher that is - and what isn't there should be in the Play Store.

So, after disabling "Secure Startup" under Settings-->Lock Screen & Security (and ensuring I had the correct drivers and ADB working and such), I...

1). Flashed the Samsung_G935x_QC_Rooted_BOOT.TAR image using the Odin3_v3.12_PrinceComsy.zip variant. The Verizon thread reports that some AT&T users had recommended the Comsy version because they found it prevented boot issues that they were experiencing when flashing with the other "plain" version of Odin that was linked. As for me, I only used the PrinceComsy version because the plain version simply doesn't run on my computer for some reason. I have no idea what the difference is between the two versions, so I've got no idea if the Comsy version may be the better way to go for USCC users as well (or if it even makes a lick of difference for anyone really), but it works.

2). After successful flash and reboot, I installed SuperSU-v.2.76-S7QC.zip via the included root.bat file and waited for another reboot to finish. I can't recall if SuperSU prompted me to download a newer version of the "su" binary upon opening the now-installed SuperSu app (as the original thread indicated it might) or not, but I didn't and neither should you apparently. As of the original post in the other thread on 7/15/2016, the "2.76-S7QC" build was the most recent version for S7 models . Since that's been over a month ago, can anyone verify if the current 2.78 version of SuperSU works with S7s (and/or USCC phones), or if there's a 2.78"-S7QC" version specifically? (I'm guessing no and no, but I lost track of the Verizon thread a while back and haven't seen any specific reference to 2.78 working or not working...)

3). From there, I downloaded FlashFire (v051, I believe) and flashed the suggested S7_or_S7Edge_Fixes_Debloater_V15.zip file, which aims to, y'know, fix some stuff and debloat the thing. I didn't manually adjust any of the "fixes" applied by the patch, and many of the apps and services killed by the "debloater" part of the script don't even come on USCC-branded versions of the phone. The instructions in the thread go on to say that some users reported problems with a handful of the fixes - Lag issues, Wifi passwords refusing to save, "Unauthorized Actions" pop-ups, and problems with VoLTE icons (the last of which isn't relevant to USC really anyway). While it seemed like the majority of VZW/ATT/other-carrier users in the thread were experiencing at least one of these issues, I didn't. There was some lag, for sure, but sporadically, and the remaining steps mostly knocked it out and I didn't need to do anything extra.

4). Next I installed a couple, but not all (initially) of the programs/settings suggested in the separate . Amplify Premium 3.3.7 and L Speed 3.1.9.7 (though I updated to the current 3.1.9.8 Beta shortly thereafter with no ill effects). Now I thought I followed the thread's suggestions pretty much exactly for these two, but when I looked just now to verify, I found that I hadn't made quite a few of the recommended changes in Amplify after all. (Probably because many of them give warnings when adjusting that the other entries hadn't, and I figured I'd play it safe). Anyway, I went ahead just now and finished everything up so that it does follow that thread's suggestions - I'll report back on it if they seem to make a notable difference. Maybe worth noting here that not all of the recommended changes are valid on US Cellular phones, so no need to worry if you can't find a few of them. As for L-Speed, I did indeed have all of the thread's recommended settings for it set, except for one, "Storage IO Tweaks: Partition Remount - Enabled." Not sure why this wasn't set, guess I just didn't see it the first time. Anyway, I've enabled it now, and since it seems to be there for "giving more permissions to the SD card," it was probably irrelevant to me anyhow since I don't currently use one.

Now, the guide suggests installing Xposed when you do all of this, along with three more apps - Greenify, ForceDoze, and LeanDroid. I decided to hold off on all the above for a while when I did it, but I'd say it's plenty safe to do it all in one go if you choose to. By the time I got around to applying the L-Speed and Amplify settings and rebooting, I had been up and rooted for at least a couple hours altogether, enough to notice that I wasn't seeing the immediate disasters a lot of other posters were finding. The most common problem seemed to be bootloops and random resets, which I hadn't encountered (and still never have really, beyond a couple of unexplained reboots once or twice that had no noticeable effects other than mild annoyance). There were also a lot of complaints about some rather extreme-sounding overheating, terribly reduced battery life, and serious lag problems - these all appeared in some degree, but seemingly nowhere nearly as bad as what people were reporting from their VZW/etc-branded phones in the thread. Plus, after making the L-Speed/Amplify changes, the battery seemed to be holding up a bit better, the phone wasn't running as warm as it had been pre-tweaking, and the lag I had experienced had calmed down from "pretty minor but definitely kinda annoying" to mostly gone. I wondered why I was missing out or getting much milder versions of all the problems mentioned by others, but by that point in the thread people were beginning to suspect Xposed was the cause. Some reported their phones working well up until installing Xposed, after which they'd begin getting bootloops or other problems. Not wanting any of that headache, I decided to just wait it out a few days and see how it held up before risking the install.

The guide also suggests at this point to turn off Wifi Scanning, Bluetooth, Location and Location History. I left the Location stuff alone, but this all seems pretty optional. It's also suggested to turn off the AOD Clock, which I left alone at the time but later disabled (and am now having issues with, but more on that later). I don't think there's any need to do the recommended disabling of all animations in Developer Options either, at least for our phones. I've left those settings at their defaults and speed's been fine.

So, since I basically took a break at this point when I was actually doing all this the first time, I'll take a break here too before getting into the next stuff I did regarding debloating and how my now-rooted-but-not-yet-real-tweaked USCC phone would turn out to actually run over the next few days...