Extremely slow might be a bit strong, however Jelly Bean has slowed down my phone to a point where I do consider a rollback to 4.0 (which by the way ran just about perfectly). I think there might be something wrong with TouchWiz, as especialy the contactscreen and the dialer are very slow.
If anyone knows a good guide on how to rollback to an older-version, please feel free share a link
I've noticed this to, I thought it was because the first time I installed it, it was the Polish release via Odin. There's loads of unroot guides that will restore to stock like this one: http://galaxys3root.com/galaxy-s3-unroot/how-to-unroot-galaxy-s3-i9300/
Great thing about this is if you have any troubles Max will help you out.
Network and GT-I9300 issues, will try my best to help.
I'm now running it through a Kies update to see if that's better, last couple of weeks was the official UK release but installed through Odin. Still seems the same very laggy even when closing folders or closing apps which it shouldn't be with a phone this powerful. I was going to keep this phone stock but may end up putting a rom on as it's getting annoying now.
Network and GT-I9300 issues, will try my best to help.
I think the problem was from the Odin update, updating via Kies will solve your problem. Don't ever update your phone via ROM/Odin, this harm your phone.
Always update from the official source.
Sent from my GT-I9300 using Android Central Forums
My s3 has become really bad since jellybean - dialler and contacts are slow as everybody else seems to be experiencing, but also generally opening apps, sometimes it's almost as if it hasn't registered the key press it takes so long. Basically in general use the phone delivers a very poor user experience. Other people on other forums are also reporting this.
A restart helps for a while but the problem returns after a day or so (sometimes less).
I loved this phone on ICS but very concerned now that it will take ages to get a fix, that the carriers will take ages to pass it on if they ever do.
PS. we have two s3s in my household. One on O2, one unbranded, both seem to be exhibiting the same issues.
factory reset is the only option boys am afraid.
Sir Marvin knows the proper samsung approved way of doin it, u may wana ask him.
its just shiz left over from ICS
global s3, UK. Ask me anything and ill reply even if its just an intelligent (or stupid) guess
youll lose a lot.
do a backup on Kies and i think that saves phone settings.. apps should re-download once you restart and log into the phone if youre on wifi but kies will back em up anyway. contacts are in the cloud so youll never lose them.
the only thing you cant save without rooting is app data/settings although you can back up custom launcher and sms app settings.
youll lose stuff like game progress, app settings that dont have a backup option.
if you wana save that stuff, root the phone then use Titanium or MyBackup Pro.
factory reset is in Storage settings.
aparently theres a proper way to do it. have u seen Sir Mervin King around the forum? samsung told him how to do it n im sure he'l help u out
global s3, UK. Ask me anything and ill reply even if its just an intelligent (or stupid) guess
I got my update today (Telcel M?xico) Did it trhough Kies and everything went smooth. I did upgrade to an UK JB prior to this and had the slowness problem, not anymore with official update via Kies. now I just want to root it. Can I do it with any I9300 JB rooting guides? or do I need a specific rooting guide?