Considering for my wife - Galaxy S 4 Q&A, Help & Troubleshooting

Hey all, been a Samsung fan for years,
Enjoy my tab 2 running cm 10.2 and her infuse running cm 10.1
Heck bought my kid a galaxy player 5.0 instead of an iPod.
I just have a few questions pertaining to this phone.
I'm familiar with how it runs its size and power drain
I would be getting it with at&t
But I am a bit lost on the boot loader issues
Am I to understand that if I have the most updated
Firmware with the newest boot loader that I can't flash ROMs?
Or is this Knox switch just a warranty voiding device?
I have been voiding warranties for years now, this doesn't bother me.
I would probably prefer not to use safe strap, as it would eat storage space. I would prefer twrp or cwm.
If I just choose to root is there anything hindering this?
Does root update the Knox counter?
My understanding is it would since it is an Odin flash.
Thanks for the responses,
I have been reading this forum hit and miss for a while now
And am just requesting some knowledge.
I know how search works I'm asking for clarifications.
Really would rather get her this phone vs the s3
And probably will even if I'm stuck with stock.
Sent from my GT-P3110 using xda app-developers app

http://forum.xda-developers.com/showthread.php?t=2470635
check the first post in this thread it should answer your questions

So simply put if you have Knox then currently there is nothing you can do but install safe strap. And root doesn't work quite right.
Thank you.
Sent from my GT-P3110 using xda app-developers app

Honestly, unless you know up front what firmware the phone is pre-loaded with, (I.E you know for certain it's running <XXUD) or unless you intend to run a purely stock phone, you probably want to steer clear of the I95x series of phones in light of Samsung's recent nonsense.
Yes, there's a fair chance some clever dev(s) might find a work around for these 'issues'. But it might take a while. I'd be really surprised if it happens this year, and it will be dependent on how much info gets leaked out of Samsung/and over what timeframe.
At the moment there's not really complete info out there, and that's why everyone's still pretty much scratching their heads trying to figure out how it all works.

I understand the waiting with your fingers crossed process. Did that with the kindle fire HD.
My biggest issue would be the need for root to tether.
Anyway thanks I'll revisit this when/if we get this phone.
Sent from my XT907 using xda app-developers app

Related

Might root

What disadvantages do I have by rooting? Had my n4 since friday
Sent from my Nexus 4 using Tapatalk 2
Have you unlocked the bootloader yet?
There are no disadvantages to root, think of it like having admin permission of your system.
Unlocking the bootloader will wipe your device, as a safety feature. On a nexus, since it's only one command to unlock, it's recommended to do that straight away if you even think you might start down the road to custom town in the future.
Sent from my Nexus 10 using xda premium
Yup...as far as I'm concerned, everyone should ALWAYS root. A - it's part of what's truly awesome about Android, B - it will more than likely come in handy at some point and C - there really isn't any reason NOT to do it.
Just do it soon after getting the device (I had my N4 for about 30 min before I started the process...within an hr of getting it, the bootloader was unlocked, it was rooted, had a custom kernel and it was ROMd) since, as stated, a wipe is usually required. And, even still, some know how with titanium can even soften that blow.
Disadvantages? Potentially void your warranty, less secure device (malicious apps that ask for SU permission), rom flashing addiction, spending too much time on XDA.
The occasional app won't run rooted - TWC TV, for example.
Sent from my Nexus 4 using xda premium
So what happens if I don't root right away? That's what makes me nervous
Sent from my Nexus 4 using Tapatalk 2
ridearoundsolo said:
So what happens if I don't root right away? That's what makes me nervous
Sent from my Nexus 4 using Tapatalk 2
Click to expand...
Click to collapse
Well, nothing. It's not a requirement.
You won't be able to use apps that need SU permission, that's all.
Unlocking your bootloader is not the same as rooting, you should do that asap if you plan on ever mucking around with your device.
lwfb said:
Well, nothing. It's not a requirement.
You won't be able to use apps that need SU permission, that's all.
Unlocking your bootloader is not the same as rooting, you should do that asap if you plan on ever mucking around with your device.
Click to expand...
Click to collapse
Why is required to unlock asap? I know about rooting its just the first time I've heard to unlock boot loader asap like does something get ruined if I hold off on unlocking the bootloader?
Sent from my Nexus 4 using Tapatalk 2
ridearoundsolo said:
Why is required to unlock asap? I know about rooting its just the first time I've heard to unlock boot loader asap like does something get ruined if I hold off on unlocking the bootloader?
Click to expand...
Click to collapse
It is not required to do it asap.
Some just recommend doing it quick because unlocking the bootloader wipes the phone. So you lose the data on there.
Story time:
Personally I always use the device for a while before I go near rooting and all the fun that comes with it, just to make sure I have a good product and stable device.
I had a Desire Z before, and had the motherboard replaced once because it had failed. When I got it back I tried it for maybe a day or two. I noticed it was a bit unstable and blamed it on the HTC software just being crap. So I rooted and flashed CM to it.
That turned out to be unstable as wel... Phone would just randomly reboot.
Unrooting and returning that Z to stock was a bit of a challenge. A guy on IRC helped me out tremendously and I'm still thankful for it, because together we succeeded.
And I could RMA once more...
So that's why I tend to wait a bit and confirm my device is solid before I go rooting.
stejoo said:
It is not required to do it asap.
Some just recommend doing it quick because unlocking the bootloader wipes the phone. So you lose the data on there.
Story time:
Personally I always use the device for a while before I go near rooting and all the fun that comes with it, just to make sure I have a good product and stable device.
I had a Desire Z before, and had the motherboard replaced once because it had failed. When I got it back I tried it for maybe a day or two. I noticed it was a bit unstable and blamed it on the HTC software just being crap. So I rooted and flashed CM to it.
That turned out to be unstable as wel... Phone would just randomly reboot.
Unrooting and returning that Z to stock was a bit of a challenge. A guy on IRC helped me out tremendously and I'm still thankful for it, because together we succeeded.
And I could RMA once more...
So that's why I tend to wait a bit and confirm my device is solid before I go rooting.
Click to expand...
Click to collapse
I agree about testing the device to see if it can hold on its own before rooting, my last phone the HTC one s was a nightmare with rooting and flashing, but I know this is much easier because I own a nexus 7 which is rooted and running codefirex
Sent from my Nexus 4 using Tapatalk 2
Hello I just receive my Nexus 4 and I Rooted 5 minutes later
Now I have a question If the Nexus 4 is Rooted it will continue receiving Android Os Updates directly from Google?
Thanks
Marioaguado said:
Hello I just receive my Nexus 4 and I Rooted 5 minutes later
Now I have a question If the Nexus 4 is Rooted it will continue receiving Android Os Updates directly from Google?
Thanks
Click to expand...
Click to collapse
Yes as long as it is stock and the kernel is stock you can receive OTA (over the air) updates. You might/will probably lose root though when the update is installed but that is not a problem, just reflash it.
Yea...you will possibly void the warranty. You can usually flash back to stock if need be and, if you break your screen or something and just want to use insurance or something, just dip it in water for an hr or so...they'll never know what you did to it other than dip it in water.
And yes, you do open the door to malware, possibly. Gotta be careful about what you install and what you grant permissions to.
The reason I say to do it soon, as was said, unlocking, (sometimes) rooting and romming will usually wipe your device. If you do all this as soon as you get the device, it doesn't matter. If you use the phone for however long, you'll lose all that data. That's the logic behind it.
I've had the phone for little over a month now and I just rooted it yesterday. I had no intention of rooting, but I got myself a Moga controller and to get the most out of that controller, it requires root.
Of course, by that time I already had all my apps & such configured exactly as I like them, so it was a bummer to have to re-download and reconfigure everything. ESPECIALLY the internal "sdcard"s contents. I was used to being able to restore and wipe without losing my personal files because all my prior phones had sdcard slots. It completely slipped my mind that the Nexus 4 "sdcard" is pretty much just its internal memory so I lost a handful of pics and other things. For these reasons, I would recommend that even if you thitnk you MIGHT want to root in the future, you might as well do it now and save yourself the time of further redownloading and reconfiguring everything a month from now.
This was a question I had so the responses have been interesting. I've rooted my previous non-Nexus devices (Mytouch 4G, HTC Sensation 4G) mostly so I could get an aosp like ROM. I had a Nexus One but never rooted it. Still trying to decide if I'm going to root my Nexus 4 because I haven't really experienced a ROM that comes without minor issues (Picasa, GPS/Navigation, etc.) The custom ROMs do have a lot of cool features though.
Sent from my Nexus 4 using xda app-developers app
The features and theming is tempting but I'm a bit worried if there's a performance drop, are there Roms that completely surpass stock speed and without bugs?
Sent from my Nexus 4 using Tapatalk 2
phon00b said:
I've had the phone for little over a month now and I just rooted it yesterday. I had no intention of rooting, but I got myself a Moga controller and to get the most out of that controller, it requires root.
Of course, by that time I already had all my apps & such configured exactly as I like them, so it was a bummer to have to re-download and reconfigure everything. ESPECIALLY the internal "sdcard"s contents. I was used to being able to restore and wipe without losing my personal files because all my prior phones had sdcard slots. It completely slipped my mind that the Nexus 4 "sdcard" is pretty much just its internal memory so I lost a handful of pics and other things. For these reasons, I would recommend that even if you thitnk you MIGHT want to root in the future, you might as well do it now and save yourself the time of further redownloading and reconfiguring everything a month from now.
Click to expand...
Click to collapse
Always backup your apps and data with Titanium Backup or with adb before unlocking your bootloader =/
ridearoundsolo said:
The features and theming is tempting but I'm a bit worried if there's a performance drop, are there Roms that completely surpass stock speed and without bugs?
Sent from my Nexus 4 using Tapatalk 2
Click to expand...
Click to collapse
If you're only worried about performance, CyanogenMod is as stable if not better than stock roms. If you're looking for optimization, I would suggest ParanoidAndroid. Most roms out there are pretty stable, except for a few hiccups, and I think the best advice is that you should try it personally and have a feel at it. :good:
I would say do it if you are interested constantly flashing ROMs. The only reason I've flashed my S2 because of the T-Mobile bloat. But then I messed more until I bricked.
The N4 is very clean and good as it is and I keep it that way.
I rooted my optimus s but all the roms for it sucksuck
Sent from my LS670 using xda app-developers app
So I ended up rooting and tried pa but am liking xylon stable a lot and about to give rasbean a try
Sent from my Nexus 4 using xda app-developers app

Debating on Rooting the S4

Im a pure n00b. I'm About to buy my first droid phone. Im very knowledgeable about iphones and the jailbreak world but I'm not sure what would be the benefit of rooting a droid phone. I've heard the droid community is pretty wide open without rooting.
What would be some benefits of rooting a phone like the samsung galaxy s4? I did see that it will allow you to tweak bluetooth to connect a ps3 controller to it wirelessly for emulators but is it anything else that XDA could share to help push me in that direction? any cool features?
Thanks in advance.
I'd say the biggest benefit from rooting is getting rid of that crap that both Samsung and AT&T put on the S4
First thing, droid phones are from Motorola. Call all others android phones. It will save some unnecessary flaming.
Pretty much still running the stock rom on mine, but used root to flash a mod that allows free wifi tethering and hot spot, and an extended power menu.
Flashing roms is also a big reason most people root phones. You can pick and choose what you want(touchwiz roms or aosp) and find one you like.
I wouldnt want an android phone without rooting it.
Sent from my SPH-L720 using xda premium
I mainly rooted for faux's kernel which removed the launcher lag and the messaging lag that occurs sometimes. I also rooted to removed all the bloatware.
Biggest reasons to root, for me personally, are custom roms, custom kernels, debloating, backing up and restoring apps, theming, overclocking, and undervolting. These are just my reasons personally. There are literally hundreds of other things you can do as a root user that you couldnt do otherwise.
The worst case scenario of rooting being, if you really dont find the benefit for yourself personally, its pretty easy to revert back to stock unrooted. These samsung phones now are basically unbrickable and flashing is really easy, especially if youve went through jailbreaking an iphone... lol rooting a samsung device is way easier imo.
Sent from my SPH-L720 using Tapatalk 2
I root for the deep-level backup capabilities, custom kernels that improve speed and battery life, Pie Control (makes navigating & using a large phone much easier), custom ROMs, mods like Hot Spot and custom themes, and deeper level security apps (firewall, find your phone, etc).
Here are the main reasons while people usually root. In no particular order.
1. Ad blocking
2. Remove unwanted apps "bloatware"
3. Custom ROMs/ advanced custom theming
4. Custom kernels and features such as nandroid backups and under/over clocking etc.
5. Tethering/free hot spot
6. Aosp ROMs
Ultimately think of rooting as taking complete control of your device. You can do pretty much anything depending on your knowledge after you are rooted.
Sent from my SPH-L720
thanks
thanks everybody. starting to like the community already. alot of quick helping people here.
I'm grandfathered in with unlimited at ATT. so free hot spot and removing bloatware talked me into it. thanks.
wotandsdwys said:
First thing, droid phones are from Motorola. Call all others android phones. It will save some unnecessary flaming.
Sent from my SPH-L720 using xda premium
Click to expand...
Click to collapse
I was thinking the same thing..lol
How much space are you guys saving when you root and get rid of all the bloatware? How much available space is on your phone before all of your additional aps?
Please read forum rules before posting
Questions and help issues go in Q&A
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djv3n0m said:
thanks everybody. starting to like the community already. alot of quick helping people here.
I'm grandfathered in with unlimited at ATT. so free hot spot and removing bloatware talked me into it. thanks.
Click to expand...
Click to collapse
There is at least one downside to rooting. You can't take the updates w/o breaking root. I've not rooted my S4 yet, but am thinking about it. I always rooted my HTC phones and it would sometimes take several months for a developer to incorporate updates into a ROM. So that makes me a little gunshy with a new phone like this, as I assume there will be a few updates in the first few months. But it seems like the dev's are much more active and on top of it with the Samsung phones, so I'm tempted to go.
Main reasons I want to go are deep backup, ad blocking and being able to tweak my settings to make it so the home button does not wake up the phone. I know, the latter reason seems silly, but it's a big deal to me.
BTW, you do not need to root to be able to tether. Check out the PDANet+ app. That's what I'm using and it works great wired or via bluetooth.
jejb said:
There is at least one downside to rooting. You can't take the updates w/o breaking root. I've not rooted my S4 yet, but am thinking about it. I always rooted my HTC phones and it would sometimes take several months for a developer to incorporate updates into a ROM. So that makes me a little gunshy with a new phone like this, as I assume there will be a few updates in the first few months. But it seems like the dev's are much more active and on top of it with the Samsung phones, so I'm tempted to go.
Main reasons I want to go are deep backup, ad blocking and being able to tweak my settings to make it so the home button does not wake up the phone. I know, the latter reason seems silly, but it's a big deal to me.
BTW, you do not need to root to be able to tether. Check out the PDANet+ app. That's what I'm using and it works great wired or via bluetooth.
Click to expand...
Click to collapse
You should be able to take otas if you have stock recovery and are just rooted, this is how it was on the S3 at least and I don't see why you can't. Also on the S3 we always got the leaks right before the otas came out so the ROMs would always have the newest builds out before the otas usually, depending on the developer, some didn't like using leaks. But Sextape would always have a leak right before the otas dropped and we had everything usually within a day or two up to a week. But the development there was amazing on the S3. :thumbup:
Sent from my SPH-L720
GiantJay said:
You should be able to take otas if you have stock recovery and are just rooted, this is how it was on the S3 at least and I don't see why you can't.
Click to expand...
Click to collapse
You can take the OTA, it will just break root. There were several threads here stating that fact here when the MDL OTA came out for the S4.
GiantJay said:
You should be able to take otas if you have stock recovery and are just rooted, this is how it was on the S3 at least and I don't see why you can't. Also on the S3 we always got the leaks right before the otas came out so the ROMs would always have the newest builds out before the otas usually, depending on the developer, some didn't like using leaks. But Sextape would always have a leak right before the otas dropped and we had everything usually within a day or two up to a week. But the development there was amazing on the S3. :thumbup:
Sent from my SPH-L720
Click to expand...
Click to collapse
Exactly what I was going to say! Sextape always came thru on the e4gt as well. The next update would always be out before the official release. So glad to see him have stuff for the s4 as well.
Sent from my SPH-L720 using xda premium
jejb said:
You can take the OTA, it will just break root. There were several threads here stating that fact here when the MDL OTA came out for the S4.
Click to expand...
Click to collapse
This is generally the case with OTA's, but every year it seems like rooting becomes more straight forwsrd, especially for Samsung. As for MDL it was a specific attribute added by Samsung to tighten up control on deeper root access that broke root, but it was hardly a locked bootloader or anything that severe. Re-rooting was as simple as loading a kernel and then Odining. At this point, most manufacturers are beginning to understand the benefits of the development community. Now if we can just get the carriers to "get it."
Sent from my SPH-L720 using xda premium
To put it very simple I root my phone to be free and to have my phone the way I wanted it not the way a company wants me to have it
Sent from my SPH-L720 using Tapatalk 2
Once you root your phone and learn all the possibilities that come along with it, you won't go back haha It's a lot of fun after knowing your stuff. reading in this forum is probably one of, if not, the best thing/s you can do

Is it worth rooting the GN3?

Hi all,
I have always rooted my Android phones since the GN1. However, with the new KNOX, is it still quite easy, safe and worth rooting the GN3?
Cheers!
Sent from my GT-N7100 using xda app-developers app
yes it is.
When I see some nice custom roms and kernels. Then I'll root mine
Sent from my SM-N900T using Tapatalk now Free
got my note 1 at the release week without warranty. rooted it, flashed with custom roms, droped it, even spoiled water on it but nothing was happened never needed a warranty. but nobody knows... everything might gone opposite way too. what i will do is get my note 3 use it for 1 or 2 months to be %99 sure that there is no faulty hardware on it and then hope for a luck and root it.
Yes.
But if you don't miss it, then don't bother voiding your warranty
Sent from my SM-N900 using xda app-developers app
Never needed to use my warranty on any device.
I always use my device for a week to see if there are any problems with the device, as with electronics if there are any problems going to develop they are likely to do so straight away.
If you decide to root, some people have had luck with samsung's warranties even with root. Depending what it is.
If the screen fails, it is likely not because of root, but if the the soc fails, they can easily blame that on the root.
Up to you, I have always rooted mine after the first week.
I have never had a phone that was not rooted until now. So far I have had no urge to root my Note 3 and the only thing I feel I am missing out on is Greenify but that doesnt bother me since battery life is so much better than my old Galaxy S2.

Any negative side effects from root on latest firmware

Title says it all my wife is probably getting the s4 from att for Christmas and I require tethering so I'm guessing I may require root.
If there are issues I'll probably go with the note 2
Sent from my XT907 using xda app-developers app
The best way to find out is to read the root threads.. If there is a problem it will be posted there.
The thing is I've been reading in another forum the unbranded one and someone told me that it had adverse side effects but I could never find proof of it so I was merely asking here.
I'm not worried about bricking or something of that nature just wanting to know if root killed something as the person in the other thread suggested it had safe guards that foiled it.
I understand Knox is a switch but these threads are overwhelmed with people already not knowing what they are talking about (like me).
Had hoped for just a -yes it flips Knox switch void warranty but other than that it's just like any other rooted device.
Or a yes the world implodes.
But from what I can tell root is fine just no twrp for me.
Keep in mind I'm just out trying to pick one not root it today.
Sent from my GT-P3110 using xda app-developers app

[Q] Knox - Does it really matter?

YES! I've used the search until my head started to spin and got no real answer to this.
I've read and read about the "Knox thing" and that it trips the flag, and so did it on my phone when I did an upgrade.
How how does tripping the Knox affect my phone?
In what way does it change it?
I know, you have no warranty, but that is always a risk you have to take with any phone/hacking. That is my decision to take.
But any REAL implications? I tried to read and read up about it and I don't see the "thing" with it?
I read and read posts about how to not trip it so I really wonder if it does something that affects the phone in a negative sense?
Does it hinder me to have root and load custom roms?
Does it hinder me in side-loading things?
What does this damn flag really do with the phone???
I read that I can't downgrade my roms from 4.2.2 to an older version but then, why should I?
I want the newest, coolest, best roms that I can get here by the amazing devs!
When I had my HTC One X I had to register on HTC-Dev to get a key to unlock the phone, so I knew what I was doing.
I was breaking the warranty and I was willingly doing that because I wanted to have custom roms.
I like to hack around and I soft-bricked more phones and times then I can remember.
In the Samsung world there is/was the Triangle away since Samsung has the counter for how many times you flashed
(but it doesn't seem to affect the phone in anyway, as far as I have read or does it?). So you might have been a bit spoiled
If this is "just" about warranty then I read that some tripped it with a normal Kies upgrade so I doesn't seem perfect.
Please, enlighten me. I can't find any good answers on this.
As a matter of fact I actually will get a new S4 soon and I'm very curious what firmware it will contain?
And this is why - Off-topic (I tend to be that).
I got a post-anesthetic amnesia after a surgery. What they told me was that I tried to start up my phone but it didn't want too (BAD Foxdoggie! )
so I threw it in the wall 2 times and then I broke it in half when they forbid me to throw it anymore.
No recollection at all, but I wish I had since breaking a phone in 2 parts isn't something you do every day
The insurance company wanted me to send in the phone for repairs and it was in at least 512 parts.
Was quite fun to go to the store and ask them to send it to service. :laugh:
Btw, keep away from the glass if it breaks! It gets razor sharp. The next day I have to pull out micro-parts from my hands that was lodged in the skin and my hands was cut all over, but then I'm good with a scalpel
So again, can someone please explain to me the negative implications of Knox?
If there are anything that will make my phone function in worse way I will make a formal complaint to Samsung here in Sweden since
I didn't buy a car to find that after a routine service, suddenly had the speed limited to 70 km/h...
I talked to my phone-company and they didn't knew what Knox was? AT ALL.
He just told me to use Triangle Away if it would break (or the same if I would jail-break my iPhone)!
So you even get instructions on what to do to make it "look" ok from your own provider since they are so well aware that people hack/root their phones.
Someone said in a post that only 1% root/jailbreak. I call that bull. But I think that more people jailbreak their iPhones then root their Androids.
But 1%? Just the fact that your cell-provider informs you how to "restore" your phone (and even asked me what rom I'm using!?!).
So maybe hard-core freaks are 1% but "normal" rooters/jailbreakers are way way way more.
It's the same with internet. Right now I have 500 Mbit and do the provider REALLY think I use that to browse Facebook faster?
So they all play a double game. At least in Sweden but I think that is quite universal?
This is my first Samsung. I'm a HTC-guy and if this Knox hinders me while other companies open up theirs instead, it will be my last.
I got a great deal on this phone and thought that since Samsung has the largest base it would be nice to see the awsome devs here.
And WOW. I was not wrong
Btw, Foxie, I love your rom, but it's just not post-surgery safe. You should add that as a warning
/Absie
Cool story bro
Sent from my Nexus 5 using xda app-developers app
Did you not spot the KNOX sticky? All questions and answers to your questions in there.
Sent from my GT-I9505 using Tapatalk
nikzDHD said:
Did you not spot the KNOX sticky? All questions and answers to your questions in there.
Sent from my GT-I9505 using Tapatalk
Click to expand...
Click to collapse
Yes, I have. It's kind of messy and is still not answering the my question.
Yes, I have read the Samsung page. I'll continue in the "real thread".
I just want to know.
Can I flash roms, can I gain root, can I load apps like before? I don't give a duck about the corp stuff. I just want to continue to flash my device and be happy with it
/Absie
absolon_se said:
Yes, I have. It's kind of messy and is still not answering the my question.
Yes, I have read the Samsung page. I'll continue in the "real thread".
I just want to know.
Can I flash roms, can I gain root, can I load apps like before? I don't give a duck about the corp stuff. I just want to continue to flash my device and be happy with it
/Absie
Click to expand...
Click to collapse
well as far as i know you can do all that as long as you don't care about the warranty, but root apps might nor work as they should(or may not work at all).
i could be wrong about all this
Sent from my GT-I9500 using Tapatalk
nikzDHD said:
Did you not spot the KNOX sticky? All questions and answers to your questions in there.
Sent from my GT-I9505 using Tapatalk
Click to expand...
Click to collapse
negrobembon said:
well as far as i know you can do all that as long as you don't care about the warranty, but root apps might nor work as they should(or may not work at all).
i could be wrong about all this
Sent from my GT-I9500 using Tapatalk
Click to expand...
Click to collapse
I just continued here to avoid comments about my sight... :cyclops:
(I did, didn't had a clear answer. Asked here. Wooboo. Will never do that again. Promise. )
KNOX is a security feature enabled by Samsung for corporate things. Does a normal end user need it probably not and should be an option. However Samsugn decided to roll it out to all phones regardless.
If you have a KNOX enabled handset, you can do as you please, root, install custom recovery, flash roms, flash kernels, however it will disable KNOX and will set the KNOX couneter to 0x1, once this is done you can not reverse it.
As an effect to warranty, it's probably country dependent. There is a warranty thread, some users have sent their phones in once KNOX has been tripped and phones have been repaired.

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