Share your experience!
Hi,
I have successfully upgrated my XPeria Go to Jelly Bean and I'm facing a big problem with phone calls :
After dialling and pressing "call", the phone is completely frozen ! It remains frozen from several seconds to about 1 minute !! During this time I have no information about the call setup progress. The call can be established, and the celled party can talk "alone" : I'm not able to know when the call is established and to hear him speaking !!! Then, my phone is no more usable !!!!
I don't know if anyone has already experienced this problem ...
Best regards.
Speaking of which (uninstalling apps) I uninstalled Swiftkey for the time being since it was consuming 30mb of RAM!!! Now I'm just using it on my Nexus 7. I then discovered that the Jellybean keyboard is also Bi-Lingual! So yeyyy! I'm happy ;D
Surely it can't be as smooth, 'smart' and awesome as Swiftkey.. right?.. Right?!
I must admit, my answer is no, it's not... but hey! If it gives me more ram... I'll just get used to it (as hard as it is, I've got the taste for swiftkey now...). ;D
(15 Minutes Later ... )
I installed Swiftkey again, sorry Swift! Will you ever forigive me?! I can't live without yoooooooou! LOL 
Oh yeah! Anyone tried those "Cache Memory Apps"?? That us SD card space for "RAM" or Swap Space whatever o call it.
I don't think the amount of RAM is an issue since other apps work just fine and similar xperia phones don't have this issue. or do they?
512 is plenty of RAM, if it's not than it's the developers who are building the software the wrong way.
Agreed! AND LIKE!
This issue cannot be blamed on a shortage of RAM, I won't buy that. Even though freeing some of it helps. The first iPad had 256mb or ram (half of the XGO) and mine is still running very smooth today after all those years of heavy use (and no reset!). Devices like the Samsung Galaxy Chat and the Cherry Mobile Magnum HD (Cherry WHAT?) have the same amount of RAM and experience no call lag issues.
It must be a compatibility issue, something from Sony is disrupting correct functionality along other apps.
And that "Choose input method" notification still isn't fixed! Why is it always there whenever I'm typing with Swiftkey? Is there any way to make it stop showing? Same for the "Location-based Wi-Fi On" notification, it's useless but mandatory.
Sorry for the offtopic:
Timmaaah! You made me google! Now you must pay!!
I googled "Cherry Mobile Magnum HD" and this appeared.
Which one is the Cherry Magnum? LOLZ! 
http://farm5.static.flickr.com/4153/5071607403_db6ec01cae.jpg
LOL! That's a fine reason to go off-topic! Excellent observation 
The issue are obvious from "deep sleep" to "wake up". The main reason is the CPU clock is not fast enough to switch from 200MHz to 1GHz, lower the CPU frequency to achieve a low power consumption so that have a longer battery life but cause lag effect. User are not allow to change the CPU clock except the phone is rooted, be caution the warranty may voided if root. To avoid the lag issue, try to wait a few seconds before receiving/making a phone call after the phone is "wake up". I hope Sony firmware engineer can optimize the code so that it can run smooth like Gingerbread.
This is strange but true... Tried waiting for a few seconds and the dialer and contacts work flawlessly... I wonder what Sony says about this... OH I KNOW!!
Sony: Have you tried using PC Companion!?
Me: Yes... It's the same!
Sony: What about full reset with SUS?
Me: Why in the... Yes I have... Same...
Sony: ... Hold on sir... I'm going to pass the call to the tec line... Please hold...
3 minutes later ...
Sony Tekky: Hello sir, my collegue has told me what happened... Have you tried using PC Companion!? (And I'm like all "Whaaaaaaaaaaaaaaaaaaaaaaaat?!") What about full reset with SUS? (And I'm all like "Toot! Phone down!!!)