Sony Xperia Arc LT15i (Upgrade from Android Gingerbread 2.3 to Ice Cream Sandwich 4 + Rooting)
Sony started to release ICS4 update for certain Xperia phones around Apr/May'2012: http://talk.sonymobile.com/message/199357#199357#199357#199357
I'm using a Xperia Arc LT15i, recently when I connected the phone to PC, the Sony PC Companion software indicated that my phone can upgrade to ICS4. However, despite following the exact steps, it keep saying there is problem upgrading my phone. I tried to visit Sony official website for help but again to no avail.....
So I Google and research around, eventually managed to upgrade it to official ICS4 rom, also rooted the device :
All thanks and credits go to: http://forum.xda-developers.com/showthread.php?t=1330314 <-- Overall I just follow this link and everything works well on my Xperia LT15i !
To unlock the bootloader through Sony official site: http://unlockbootloader.sonymobile.com/instructions <-- Optional
For rooting, I just download and follow steps from : http://uploaded.to/file/2gt28pco <-- Optional
My Xperia Arc LT15i on ICS4, unlock bootloader & rooted !
My main intention to root the device simply because the device's internal size is only 380MB, it runs out space easily, especially those apps updates.
After rooting, I installed the Link2SD app so I can install and update directly to MicroSD without going through the internal again !