Database Users

Am I rootable?

Im brand new to the android world. Finally left apple and switched to the better side. Been doing some research before rooting and installing a rom on my device. I just want to check and see if this is okay.
I see that if you have MF3 you cant do any of these.
I believe this does mean I have mf3 but i want to double check.
under about device it says my baseband version is I337....MF3
and my build number is ...........MF3.
So is there nothing I can do to my phone just yet?

dankify said:
Im brand new to the android world. Finally left apple and switched to the better side. Been doing some research before rooting and installing a rom on my device. I just want to check and see if this is okay.
I see that if you have MF3 you cant do any of these.
I believe this does mean I have mf3 but i want to double check.
under about device it says my baseband version is I337....MF3
and my build number is ...........MF3.
So is there nothing I can do to my phone just yet?
Click to expand...
Click to collapse
With MF3 only option is root only
Sent from my SAMSUNG-SGH-I337 using Forum Runner

dankify said:
So is there nothing I can do to my phone just yet?
Click to expand...
Click to collapse
welcome to android. glad to have you here but sorry on such poopy circumstances. to answer your question, at the moment there is little you can do. the MF3 build is in fact rootable, but i do not recommend it to anyone, especially a new user. if you were to root your device and have any problems at all with it, there is no way to unroot or even really get your problem straightened out. without going into all the details, it's just too risky at this point for me to recommend rooting your device on this build number simply to allow you to remove a few apps you dont want on the phone. you cannot even install a custom recovery or flash any ROMs. sorry your entry into android had to begin this way. i've seen several users that are still within their 14-day return window, take their devices to at&t to exchange for a different color S4. when doing that, they have the rep check 1 or more S4's and make sure they're getting a device with MDL (if the store even has any).
stay posted as there will be a fix for this at some point. cheers.

Getting my bootloader unlocked

My question is I have a s4 without being on a contract and I let att unlock my boottloader can I install cwm or teamwin on my phone and I am looking to install the liquidsmooth rom. Or do you guys recommend any other rom that allows me to overclock the cpu and gpu??

What firmware version are you on? If you have MF3 or higher, no you can't unlock the bootloader. If you have MF3 or higher you can't install a custom recovery other than safestrap. Most custom roms have cpu control, and if they don't there are always root apps.
Sent from my SGH-I337 using Tapatalk

The AT&T S4 does not have an unlocked bootloader. To find out more information about the phone and what you can or can not do, read the "pinned" threads in the General and Q&A sections.

Understand Its not unlocked but since im not under contract of any sort I figured I could get them to unlock it? That was my main question, I know you could go to AT&T before all the bs came up with there security pay a fee and get it unlocked? I am already rooted, I read up on safestrap as much as I could but still I hear its ok and not ok to do so. I root every phone I own and I now work with Verizon and getting the note 3 for my agent line and plan on rooting it as well. But right now I guess I would like to find a way to where I can get this thing where I want it. I had a htc one before the s4 but had tons of problems with the speaker blowing after 4 phones I requested to s4 and got it. I do have M3 software as well, if you have safe strapped your s4 what roms do you recommend? I know only some work with safestrap and I really like the liquidsmooth rom.

faststang71 said:
Understand Its not unlocked but since im not under contract of any sort I figured I could get them to unlock it? That was my main question, I know you could go to AT&T before all the bs came up with there security pay a fee and get it unlocked? I am already rooted, I read up on safestrap as much as I could but still I hear its ok and not ok to do so. I root every phone I own and I now work with Verizon and getting the note 3 for my agent line and plan on rooting it as well. But right now I guess I would like to find a way to where I can get this thing where I want it. I had a htc one before the s4 but had tons of problems with the speaker blowing after 4 phones I requested to s4 and got it. I do have M3 software as well, if you have safe strapped your s4 what roms do you recommend? I know only some work with safestrap and I really like the liquidsmooth rom.
Click to expand...
Click to collapse
All your answers will be in this thread right here including links to download safestrap and what Roms will work for it. In the end its user preference than outing out who has the “BEST" ROM. Its all based on personal preference on what is good for you and not. Take your time to read and flash and play around with them.
http://forum.xda-developers.com/showthread.php?t=2428254
Sent from my SAMSUNG-SGH-I337 using xda premium

I believe AT&T unlocked your SIM not the bootloader as they don't do that at att
Sent from my SAMSUNG-SGH-I337 using XDA Premium 4 mobile app

May I suggest maybe changing the title of your thread OP? Its very mis-leading. I'm sure that with the knowledge of the people that responded to you and the links that were provided, you understand that you can not unlock the bootloader at this time.

Very confused about MF3

I just bought the HTC One for $200, but then I saw that Best Buy had the Samsung Galaxy s4 on sale for $50. I did not know which one I wanted and was truly torn between the two and ended up buying the HTC but if I can save $150 I will gladly get the s4. My only problem is that as I've been reading up on cs4 forums to make sure that I would be able to unlock root and flash custom roms I had came across what seems to be the problem with an AT&T firmware update known as mf3. If I cannot root and flash custom kernels and roms I do not think I will take advantage of the offer from Best Buy. My problem is that even after all the reading I cannot figure out whether it is possible to root and flash custom ROMs and kernels to the new version from AT&T, known as mf3, or if it is still not possible, or if it will be possible very soon so that I'm may use Android 4.4 Kit Kat on the phone or any custom Rom I wish. Can someone please clarify this for me as soon as possible because my time to return the HTC One to AT&T is coming close to its end?
Sent from my HTC One using Tapatalk

You can root and flash some roms using safestrap. But it's very limited. Imo I'd stay away from the s4

It's there any progress toward cracking MF3? I've had a one x for pat year and kinda wanted a change and I love the screen on the s4. If you had to choose between the s4 and the HTC one taking into consideration the mf3 problem, which would you choose? And which would you choose if there was no mf3 problem?
Sent from my HTC One X using xda app-developers app

If you can find a S4 with MDL or earlier firmware it's a excellent phone. Personally if it has MF3 or later I wouldn't bother. But that's just my opinion.

You might as well get rid of the One as well. It's just as locked down.
Sent from my SAMSUNG-SGH-I337 using XDA Premium 4 mobile app

Untrue, about HTCone being just as locked down. It can have it's boatload unlocked quiet easily and if you want to, although it's not necessary, you can even do s-off to get full unbridled access. I previously had a HTC one x and also from everything I've read it seems AT&T went out of there way to lock down s4 tight , just like they did to the one x but eventually the devs got it. I do want the s4 though,even though this phone is awesome(HTC One), and I can live with no custom Rom for a while but I can't go without root. So if I get a s4 with mf3 will it still be able to be rooted ? I've read up on it but don't understand what everyone is talking about when they say if the phone is encrypted or notand it seems to be random.
Sent from my HTC One using Tapatalk

So sick and tired of reading about MF3, or MK2 constantly on these forums. If you want to buy an S4 on AT&T look for an MDL one on eBay. It's not that hard, really.
Or buy the T-Mobile variant or International version.

Thanks for your kind response to my honest question mattmjb0188. I can't get a t mobile or international variant bc I'm on a budget. I will use my upgrade to get the phone at best buy for $50, and the condition of this price is that it must be a contract renewal/upgrade, which is another reason I can't get diff version of the phone. Did you even read the op? I would love to get one brand new out of the box with mdl but the odds of that are slim hence why I asked the question in the 1st place. So if you can't help or don't like the question then don't respond, but I do thank you for your info about the other variants that don't have issues, it just doesn't help me.
Sent from my HTC One X using Tapatalk

Rad ryan said:
Thanks for your kind response to my honest question mattmjb0188. I can't get a t mobile or international variant bc I'm on a budget. I will use my upgrade to get the phone at best buy for $50, and the condition of this price is that it must be a contract renewal/upgrade, which is another reason I can't get diff version of the phone. Did you even read the op? I would love to get one brand new out of the box with mdl but the odds of that are slim hence why I asked the question in the 1st place. So if you can't help or don't like the question then don't respond, but I do thank you for your info about the other variants that don't have issues, it just doesn't help me.
Sent from my HTC One X using Tapatalk
Click to expand...
Click to collapse
Anyone new on these forums just asks over and over about MF3 and the Android 4.3 update. Basically, if you get an S4 with Mf3 or later firmware, you are pretty much stuck on stock. Then we have noobs who don't read and attempt to root their MF3 phones and brick them.
On pure stock, the S4 is a bad phone. The software is very laggy and needs a lot of improvement. I was one of the early adapters when it first came out. The phone was a nightmare with MDB and MDL firmware. Mf3 made slight improvements, but not enough.
I would not even invest in buying this phone right now. Most development for it has died down because of the restrictions. Developers are moving on. Those of us with MDL firmware (like myself) won't see much continued support for Loki nowadays anyway. If the bootloader could be unlocked, I believe it would have been unlocked by now. All these workarounds are very limited, and dangerous.
Personally, I wouldn't even buy the phone at this point. Scrape the funds together for either the T-Mobile S4 or Note 3.

Get the nexus 5, you'll be very happy

Thank you very much for that answer, that was an excellent answer. Although I'm not a noob bc I've been doing this stuff for years and been a member for years.I did the trading but I am not familiar with Samsung at all bc the last Samsung I had was a captivate. It's there a lot of active development for the t mobile variant? I'm guessing it's probably around $600, right? Lastly do you think that there will be a solution to the lock down of mf3 and later in the next few months?
Again thanks for your very helpful answer.
Sent from my HTC One X using Tapatalk

Rad ryan said:
Thank you very much for that answer, that was an excellent answer. Although I'm not a noob bc I've been doing this stuff for years and been a member for years.I did the trading but I am not familiar with Samsung at all bc the last Samsung I had was a captivate. It's there a lot of active development for the t mobile variant? I'm guessing it's probably around $600, right? Lastly do you think that there will be a solution to the lock down of mf3 and later in the next few months?
Again thanks for your very helpful answer.
Sent from my HTC One X using Tapatalk
Click to expand...
Click to collapse
The development for the AT&T S4 has died down. In my opinion, no one will ever unlock the bootloader for it. Maybe someday with some future device, but not this device. The closest we got was with the loki method, which was great. But that's long gone now.
Look on negri for the T-Mobile variant. I think its M919. I'm not sure. T-Mobile developers have been able to make great roms for the device, instead of wasting so much time to find a workaround. Maybe even try T-Mobile out and see if they've improved in your area. They got a lot better in my area, but still a lot of EDGE.
If I were you, I'd go for the Nexus 5.

Rad ryan said:
Thanks for your kind response to my honest question mattmjb0188. I can't get a t mobile or international variant bc I'm on a budget. I will use my upgrade to get the phone at best buy for $50, and the condition of this price is that it must be a contract renewal/upgrade, which is another reason I can't get diff version of the phone. Did you even read the op? I would love to get one brand new out of the box with mdl but the odds of that are slim hence why I asked the question in the 1st place. So if you can't help or don't like the question then don't respond, but I do thank you for your info about the other variants that don't have issues, it just doesn't help me.
Sent from my HTC One X using Tapatalk
Click to expand...
Click to collapse
Heres my suggestion, if you want the s4, get it from best buy than sell it unopened for as much as you can and than with the money you get buy a tmobile or i9505 international variant...(not i9500 or the verizon or sprint one)
The tmobile variant is probably your best bet, the tmobile variant supports all of ATT service bands so youll have no issues with reception or internet. The tmobile variant can flash roms from any of the other s4 variants (verizon sprint att i9505...just not any roms from the i9500)
So in other words if you get the tmobile variant you dont have to worry about a dead dev scene as you can always flash roms from a differnt carrier...only thing is you will probably have to set up your apns for att rom flashes
Hope that helps you
And on another note if you decide to stick with the ATT s4, every firmware can be rooted
Mdb has real recoveries, so you can flash anything as long as you "loki" the kernel - Unfortunately I do not think there are any stores that are selling phones with this firmware
Mdl has real recoveries, so you can flash anything as long as you "loki" the kernel...Unfortunately it is pretty much impossible to find a phone with this firmware in any store now
Mf3 has safestrap which is kinda like a recovery, with it you can flash any touchwiz based 4.2.2 rom (stock roms) or any 4.2.2 Google Phone Edition (aka GPE, which is an aosp experience S4, no bloatware no samsung features, its like having a nexus in the body of an s4) rom...NO CUSTOM KERNELS, NO AOSP ROMS (no cyanogenmod) - this is the firmware most phones come with
Mk2 (latest firmware) recently got a beta safestrap...as of now you can flash some 4.3 touchwiz stock based roms, alot dont boot yet, and the GPE 4.3 rom doesn't boot with it either. As it becomes stable it should work identical to the one for mf3 - phones will probably start coming with this one soon
In other words, safestrap allows you to run roms that are built off the same firmware version as your stock rom, safestrap flashes no kernel, so whatever rom you flash has to be compatible with the stock kernel of your current firmware
Sent from my SAMSUNG-SGH-I337 using Tapatalk
---------- Post added at 08:44 PM ---------- Previous post was at 08:40 PM ----------
Rad ryan said:
Thank you very much for that answer, that was an excellent answer. Although I'm not a noob bc I've been doing this stuff for years and been a member for years.I did the trading but I am not familiar with Samsung at all bc the last Samsung I had was a captivate. It's there a lot of active development for the t mobile variant? I'm guessing it's probably around $600, right? Lastly do you think that there will be a solution to the lock down of mf3 and later in the next few months?
Again thanks for your very helpful answer.
Sent from my HTC One X using Tapatalk
Click to expand...
Click to collapse
They actually seem to be getting close to another work around which will allow you to flash any rom or kernel using safestrap...turns out theres a feature in the 4.3 mk2 kernel which allows unsigned drivers to run, in theory they can compile a kexec driver for the kernel which would allow you to use any kernel thus allowing the flash of any rom...theres a how-to thread in the original development section with more info, however...its not a guarentee we will see this anytime soon, as you never know what issues they may run into...but something to look into if your interested
EDIT: actually heres a post from the thread i mentioned which pretty much sums up how we hope this "exploit" will work as far as kernel flashing goes http://forum.xda-developers.com/showpost.php?p=48703510&postcount=10
Sent from my SAMSUNG-SGH-I337 using Tapatalk

With all that said; how come I have the MF3 baseband my s4 (jflteatt), and I still have a custom recovery with the ability to flash different roms and kernels? Is it because I installed the custom recovery on an earlier baseband and then it got updated to a newer baseband but still kept recovery?
I only found out I had MF3 on my phone now because I couldn't flash a different recovery anymore.

Yes
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noel_leon said:
With all that said; how come I have the MF3 baseband my s4 (jflteatt), and I still have a custom recovery with the ability to flash different roms and kernels? Is it because I installed the custom recovery on an earlier baseband and then it got updated to a newer baseband but still kept recovery?
I only found out I had MF3 on my phone now because I couldn't flash a different recovery anymore.
Click to expand...
Click to collapse
It is literally impossible to have officially updated through OTA while on a custom Recovery. What I suspect has been done is the same as my phone. I got an MDL device and quickly installed TWRP and a custom ROM. As new updates came out, I flashed just the baseband. So now, I have a 4.4 ROM with the MK2 baseband and am able to install anything I like.
If I were to have ever done an OTA, I would no longer be able to have a custom recovery because of a blown Qfuse.
Please don't try to say that what you have is the only phone with OTA MF3 and custom recovery.
The only way to have anything like that is through SS and that is not a true recovery. If you do have that, you can only install certain ROMs not including AOSP, AOKP, MIUI, or CM.
Sent from my SAMSUNG-SGH-I337 using XDA Premium 4 mobile app

When did I ever say I was the only one? I asked a simple question that I mostly had the answer to already; which in turn was answered by a simple "Yes" from HiTideBlastoise.
And I never said anything about OTA either. I said I had installed custom recovery on an earlier baseband and then my baseband was updated but recovery was still intact.

I never said you did say that. It was preemptive. Secondly, you make it out to seem like you did nothing to update your baseband. You are making it seem like it just happened. Well, that can't happen without either updating the entire phone or flashing it yourself. The funny thing is the baseband means nothing when it comes to recoveries and flashing ROMs. It can only be used as a possible sign on a stock device as to what version one is running. On a modified device, like yours, it is worthless information on the version of Android. Like I said before, I have 4.4 with MK2 as my baseband. How can I install ROMs. Not because it updated my baseband after I already have a custom recovery... But because I never took an OTA and made it do the stuff I wanted.
Basically what I am saying is that you need to be clear with what you say. Everything you said makes it sound like your phone did it all by itself without you or someone else making it the way it is. There is no other option. You have to have done something to have a custom recovery and an MF3 baseband with pre MF3 bootloaders.
Sent from my SAMSUNG-SGH-I337 using XDA Premium 4 mobile app

I agree with graydiggy that the only way to still have a custom recovery and mf3 baseband is that you either flashed an mf3 tw rom with a modem or a a standalone modem to your mdl software. If you took the "OTA" successfully, you will definitely have a locked down bootloader now.
Sent from my SCH-I545 using xda app-developers app

[Q] KIT KAT on contracted Samsung S4 AT&T i337?

I have had my S4 since switching to ATT in late November and have been following the XDA forums very closely since then. It was thanks to the XDA forums that I was able to root my S4.
However, no matter how far, wide, and meticulously I look on the site, there is no mention of the existence of running KIT-KAT on the i337 S4 for AT&T, save for the Google Play Edition and the version with the octacore etc.
I know these forums are strict (and should be) about questions being asked more than once, but I am not asking when KITKAT will be released through AT&T or even Samsung because I honestly don't care. I simply want to get KitKat on my device running with relative stability. I know there are custom roms out there, but most of them were released...a month ago or so? MAYBE I'm missing something, but if anyone here is in similar shoes, I would appreciate it if you'd echo my sentiments/request to find out if it can be done and how.
Anyone who knows how I can learn more about loading ASOP onto my i337 S4, I would greatly appreciate it. If the limitation is a locked boot loader that you CANNOT get around (excluding safestrap), do let me know! I'm sure a lot of people would benefit from the answer to this question.
Otherwise I'm going to go buy the Google Play Edition of one of the Android devices that has an unlocked boot loader.
Cheers,
Justin

justintime001 said:
I have had my S4 since switching to ATT in late November and have been following the XDA forums very closely since then. It was thanks to the XDA forums that I was able to root my S4.
However, no matter how far, wide, and meticulously I look on the site, there is no mention of the existence of running KIT-KAT on the i337 S4 for AT&T, save for the Google Play Edition and the version with the octacore etc.
I know these forums are strict (and should be) about questions being asked more than once, but I am not asking when KITKAT will be released through AT&T or even Samsung because I honestly don't care. I simply want to get KitKat on my device running with relative stability. I know there are custom roms out there, but most of them were released...a month ago or so? MAYBE I'm missing something, but if anyone here is in similar shoes, I would appreciate it if you'd echo my sentiments/request to find out if it can be done and how.
Anyone who knows how I can learn more about loading ASOP onto my i337 S4, I would greatly appreciate it. If the limitation is a locked boot loader that you CANNOT get around (excluding safestrap), do let me know! I'm sure a lot of people would benefit from the answer to this question.
Otherwise I'm going to go buy the Google Play Edition of one of the Android devices that has an unlocked boot loader.
Cheers,
Justin
Click to expand...
Click to collapse
What version are you currently running. Go to about phone and post your baseband version. If the 2nd to last digit is f or higher you can't get kit kat yet. If it is before f then you are free to do whatever you want., If you are rooted you can just download rom manager from the play store and flash a recovery the easy way. Then get cyanogenmod or something for your device.

failedjedi said:
What version are you currently running. Go to about phone and post your baseband version. If the 2nd to last digit is f or higher you can't get kit kat yet. If it is before f then you are free to do whatever you want., If you are rooted you can just download rom manager from the play store and flash a recovery the easy way. Then get cyanogenmod or something for your device.
Click to expand...
Click to collapse
Thank you for your reply!!!
That is most unfortunate, since it is i337UCUEMK2 - even if I did some crazy stuff to go back to MF3, I'd be right at f anyway. ROM Manager and flashing a recovery the easy way seemed simple enough and I was going to do that but it ended up not working, then I tried using Goo Manager and that soft-bricked my phone and I spent hours getting it back to MK2 again. It's back to the way it was, but I still want to update to Kit-Kat.
Btw, could you tell me why it isn't possible because of my baseband? Thanks failedjedi, and anyone else that can offer useful information.
Cheers,
J

justintime001 said:
Thank you for your reply!!!
That is most unfortunate, since it is i337UCUEMK2 - even if I did some crazy stuff to go back to MF3, I'd be right at f anyway. ROM Manager and flashing a recovery the easy way seemed simple enough and I was going to do that but it ended up not working, then I tried using Goo Manager and that soft-bricked my phone and I spent hours getting it back to MK2 again. It's back to the way it was, but I still want to update to Kit-Kat.
Btw, could you tell me why it isn't possible because of my baseband? Thanks failedjedi, and anyone else that can offer useful information.
Cheers,
J
Click to expand...
Click to collapse
With mf3 they locked down the bootloader. So before mf3 you were able to put a custom recovery and custom roms. Since MF3 no one has figured out how to bypass it yet. With mf3 you can use safestrap to sort of get some custom roms, but it still needs to boot the stock kernel as you can't yet use a custom kernel. As a result you are limited to only 4.2.2 Touchwiz based roms working. Now safestrap has a beta for newer versions, not 100% sure what it does and does not support yet as I'm sticking with my mf3 and a 4.2.2 jellybean rom. But the beta is new and probably still buggy.
But basically since you need the stock kernel, you are limited to only the android version your current stock version is.

Yeah as an android developer, I accept that, but am not going to permit it to remain true. This might take awhile...
Sent from my SAMSUNG-SGH-I337 using XDA Premium 4 mobile app

If you are a developer there are bounties out for someone to get this working on mf3>
I don't have that issue but good luck if you try--:good:

Thanks! Didn't really know there were bounties for that - worthwhile ones anyway given that im dev apps and messing with AOSP and mainly my att s4 every chance I get.
Actually id be doing it for mk2, and if it becomes apparent that mf3 is easier to do it with ill do with that since I'd just DANGEROUSLY use Odin to go back, root, sideload titpro and block the sht out of the autoupdate. From what ive seen, the intermediary version between mf3 and mk2 might be most likely. This is all conjecture anyway. Sooner or later I will allow people to be free even with contracted or used phones.
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New S4 new to ROMS and add ons

Hi I just got a new sprint Galaxy s4. I had a Samsung infuse 4g that I rooted and unlocked (which btw was hard to do for a newb way back then) but I never flashed a rom. To be honest I was afraid that I would destroy the phone. They are not cheap. I still have the infuse, so I guess I could practice flashing roms on that one but is it basically the same process? I just really really do not want to destroy my beautiful phone. Is it risky to flash ROMS or put other stuff in the phone? Thanks for the advice. This is an awesome site.

*Anything* you flash to your phone carries a risk (however minute) that it'll brick the device. The root method may be different, but for the most part ROM flashing is the same across any Android device.
IMPORTANT: Check your device model, since there are two variants of the Sprint S4 out there (SPH-L720 and SPH-L720T). The 720T doesn't work with all ROMs, and (last I checked) you lose the Spark connectivity, but 1x/3G/LTE will still work. I have one of the old models before Sprint started rolling out Spark, so I haven't really been keeping up with that part of it.

emeralds5668 said:
Hi I just got a new sprint Galaxy s4. I had a Samsung infuse 4g that I rooted and unlocked (which btw was hard to do for a newb way back then) but I never flashed a rom. To be honest I was afraid that I would destroy the phone. They are not cheap. I still have the infuse, so I guess I could practice flashing roms on that one but is it basically the same process? I just really really do not want to destroy my beautiful phone. Is it risky to flash ROMS or put other stuff in the phone? Thanks for the advice. This is an awesome site.
Click to expand...
Click to collapse
once you get the rooting done here is a great place to start looking for ROM's
http://forum.xda-developers.com/showthread.php?t=2303917

cyberweasal said:
once you get the rooting done here is a great place to start looking for ROM's
http://forum.xda-developers.com/showthread.php?t=2303917
Click to expand...
Click to collapse
thanks for replying. I posted a question on the rooting thread regarding the s4. I was wondering about rooting it with my
Android version. I believe it's the latest but was not sure. Do you know if it's relatively safe to try that or are there issues like boot loops? Maybe I should leave well enough alone because I doubt I could fix a brick. These are really nice phones...thanks for your help

emeralds5668 said:
thanks for replying. I posted a question on the rooting thread regarding the s4. I was wondering about rooting it with my
Android version. I believe it's the latest but was not sure. Do you know if it's relatively safe to try that or are there issues like boot loops? Maybe I should leave well enough alone because I doubt I could fix a brick. These are really nice phones...thanks for your help
Click to expand...
Click to collapse
i had no problems. that being said. make sure you also have a stock rom down loaded on the phone or on a pc to fall back on, that way if you do boot loop you can just flash that. also once rooted make a backup!
you can root without doing a new rom or even choose a rom thats mostly stock with minimal changes its up to you how deep you go.
first thing if first once you root if you have KNOX you WILL flag the knox warranty count by 1 and that is not reversible yet.
good luck