Share your experience!
I noted the following problems....hope others having problems will post here to get a good response from sony...
1. My phone is slow even though I uninstalled most of the applications I used in 4.1.
2. (maybe the same problem) my remaining ram is around 190 and 200 even though i have disabled most of the applications.
3. phone in battery saver and stamina mode on for 8 hours battery draind 8 percent..( 4.1 It never happened)
4. Screen is sort of blinking when waking up...
5. Led notification light keeps on during the call....
6. Autobrightness is not working as promised to correct it.....
is it worth to have a phone like this???????????
shame on you sony you took so long for this update, finally to produce a **bleep** like this...????
welcome to our party my friend... unfortunately most of the people have the same problems after the update 
As many people, i have serious problems with my phone afer the 4.3 update. Phone is too slow now. Apps just crash from time to time. Even if an application works, takes more than 30 secs to start running after pressing the shortcut. Sometimes i can't open my contacts, messages or incoming calls list because phone is freezing. Sometimes i can't even have a call because i have no signal and i can only have emergency calls (my signal was no less than 2 lines b4 the update). Also i am getting random restarts sometimes. I have reseted phone to factory settings 3 times, i reinstalled the update with SUS with no any improvements. So i am asking u guys. Are u happy with the update and u gonna keep it? Or are u gonna give us a hot fix soon? Is there an option to intall 4.2 again? I really don't trust this phone anymore. I'm sure i'm missing calls or messages and can't communicate anymore with other people...
I'm having the same problems here :'(
So much time and effort and I don't know how do they send us something like this :S
I much prefer that they told me their having some issues with some bugs than releasing a really faulty firmware :S
PS: Sorry my english :x
I was also having lots of problem after the update. But after repairing my phone most of the problem despaired. But two major problem is still present. During installing, update installing and unistalling an app the phone freezes and does not respond to touches. This is a new kind of problem which I never faced in 4.1.2. And while the wifi range is fixed, now it just cant maintain the connection to internet for more than a minute, even though it shows wifi signal is full.
It is strange that phones purchased in different parts of the world have so many different problems although it is the same model of the phone.
For instance, I haven't notices any real improvement in wifi range, however, my phone's wifi connections are stable both at home and at work.
Guys, you may not like this but this isn't a sony issue, its an android issue.
Read other forums for your carrier or a different phone vendor, ALL will show some people having issues and slowdowns/battery drain etc. after an Android update.
The resolution almost everytime is to do a reset of your device, i.e. factory reset and re-set it up and all their issues are resolved, I also have a S4 and had lots of issues after updating to 4.3, a factory reset fixed it.
With android (assuming you have set it up) everything should be backed up to google anyway, thus as soon as you enter your details again, it'll download all your contacts / apps etc.etc.
Make sure all your music and photos are saved to your memory card and all will be fine.
Sure i agree its RUBBISH - but its not really Sony's fault it just seems the android way unfortunatly... (which is why some people dont have an issue and their device is working fine after the update)
Try it - you just might be surprised 