Nowadays, it's easy to root your Optimus S and install a custom ROM that will give you much better performance, more RAM for applications & data, etc. Following is a step-by-step guide for dummies (like me).
This guide is only for people on software version ZVD or ZVH, so figure out which software version you have installed first. (I may write a ZVC guide later after I update a couple ZVC phones.) From the home screen, hit the "settings" button, select settings, "About phone". The software version should end in ZVD or ZVH.
Make a note of which one. This is really important because certain ROMs only work on certain baseband software versions. (Loading a mismatched ROM wouldn't damage your phone but you probably couldn't use it for phone calls or 3G. You could reflash the appropriate ROM, but you don't want to waste time doing that.)
I'm going to assume that you're using a PC, that you have a working
USB driver for your phone, that you know how to connect your phone to your PC via USB, and that you know how to move files between your PC & your phone's SD card.
Here we go:
1) Make sure that you have about 500MB of free space on your SD card. You'll only need it temporarily, so if you don't have enough space, you might want to temporarily move music files to your PC.
2) Rooot your phone and install the Xonia CWMA custom recovery.
--A) Downoad
optiauto-sfx.exe to the C: drive of your PC.
--B) Make sure your SD card is installed.
--C) Make sure USB Debugging is enabled. Menu->Settings-> Applications->Development->USB debugging.
--
D) Make sure USB Storage Mode is off. (Drag down the notification bar."USB Connected" should be green.)
--E) Make sure that you have the LG/USB drivers installed.
--F) Make sure that the phone is connected to USB port and recognized by the PC.
--G) Make sure that the phone is turned on.
--H) Make sure that the phone screen is unlocked.
--I) Launch Optiauto.exe on your PC. Select option "A". The program will run and it will let you know whether or not it worked. If it works you'll have root access to your phone (thereby allowing you to run certain programs) with the Xonia Custom Recovery installed. (A custom recovery is a little program that you can invoke at power-on that does stuff like backing up, restoring, or loading firmware, etc.)
3) Install Titanium Backup (free app) from the Play Store. Start it. Give it root access and do whatever it tells you to do at startup. Then restart it, select "Backup/Restore", Hit the "Settings" button and select "Batch". Then hit "RUN Backup all user apps + system data". Now you've backed up all your apps and data so that you can easily restore it all to any new custom ROM that you load.
4) Download a custom ROM to your PC and then move it to the top level of your SD card. For ZVH you probably want to choose
gROM or
HydroROM. (I slightly prefer HydroROM.) For ZVD you probably want to choose
Reborn ROM,
sROM, or
Kraven's CM7 ROM. (I chose RebornROM.)
5) Do a "Nandroid backup". A Nandroid backup creates an image of your current ROM for added safety. If you save this you can always return your phone to EXACTLY the way it was at the time of the Nandroid backup by doing a "retore" of that Nandroid backup. So don't fear! To do a Nandroid backup:
--A) Turn off the phone.
--B) Boot into recovery mode by simultaneously pressing the power button,
----Home-button, and volume-down button until you see the "LG" screen.
----After several seconds you should be greeted by the Xonia Custom Recovery main menu.
----(Note: You'll move the highlight up and down with the volume up/down keys.
----Select with the "Settings" key, and go back with the "Back" key. The "home" key toggles the screen off & on.)
--C) Select "backup and restore".
--D) Select "backup". (It'll take a a minute or two and give your some feedback. Don't worry.)
6) From Xonia's main menu, select "wipe data/factory reset" and confirm. Then select "wipe cache partition" and confirm.
7) From Xonia's main menu, select "install zip from sdcard", then "toggle signature verification" to "off", then "choose zip from sdcard" and select the custom ROM that you loaded onto your SD card. Confirm. The ROM will load. Sit tight. This takes a minute or two.
8) Reboot into your new ROM. The first time (only) takes a really long time. Don't worry.
9) Walk through the set up procedure. Turn on WiFi if available. And install Titanium Backup from the Play Store.
10) Launch Titanium Backup. Give it superuser access and do whatever it says. Select "Backup/Restore", hit the "Settings" button, select "Batch", and "Restore Missing Apps and All System Data".
11) Enjoy! If you didn't choose gROM, consider installing "No Frills CPU Control" from the market so that you can overclock. (You should be able to overclock to at least 806MHz-- maybe faster depending on your phone, but if it starts glitching or crashing, then back-down the clock speed.) And with all that extra speed and memory, you may want to consider downloading and installing Adobe Flash for ARMv6 from
here. You may also want to consider installing FoxFi (free app) which gives easy WiFi tethering/Hotspot capability.
12) Clean up. From your PC (via USB) you may want to move your Nandroid backup onto your PC for safekeeping and to free up space on your SD card. You will find your Nandroid backup on your SD card under "clockworkmod/backup". It will be a folder named with a date. DON'T RENAME IT (or the checksum won't work). You may also want delete the custom ROM's zip file from your SD card (since that ROM is now loaded into your phone). And if you moved music (or something) off of your SD card, you may want to move it back.
That wasn't so hard was it?