[Sony Xperia P, U, Sola, Go] satya-1998:
Hello everybody, today I present my guide or actually the procedure of modifications presently installed on my Xperia U.

1. Grab your Xperia U (I presume it is bootloader unlocked, rooted and installed Stock ICS based firmware)

2. Battery Supercharging-

a. Let your battery charge to 100%

b. Unplug charger and Reboot into CWM and wipe battery stats

c. Reboot into system and use phone as normal until battery is exhausted. (Now your battery is calibrated)

d. For maintenance of life of battery pack thereafter, let battery drain to not below 10%

e. Always charge battery short of 100% i.e. 85-95%

f. Once in a month, shut down your phone at 30-60% charge, remove your battery, and just leave it outside the phone for an hour or so.

Be compassionate, as Gandhiji had said :)

g. If you want to recalibrate your battery, follow steps 2a-2c. Recalibration for Li-poly is not that essential, since it has no memory but you can do it once a month or after flashing a new ROM.

h. Never leave your battery discharged for very long. Your Li-Poly battery will suffer a deep discharge.

3. CPU Control

a. Download BrainsKernel or Munjeni's Kernel

b. Install it using flashtool or fastboot (i presume you know how to do so)

c. Download your favourite CPU Control App (setCPU, noFrills CPU Control etc.)

I recommend CPU Tweaks as it gives you info on both cores at the same time and also has the time graph for when CPU is asleep (setCPU lacks that)

d. My recommended governor setup-

[Try to use a governor with inbuilt hotplug technology (hotplug means ability to control cores i.e. turn of second core when not required and turn it on when required) Eg. Hotplug, Lulzactive, PegasusQ, Hotplug etc.]

For normal use-

LulzactiveQ 800/200 MHz

For Music(Screen Off)

OndemandAX 800/200 MHz

For Gaming(Dead Trigger etc.)

Ondemand/Hotplug 1000/200 MHz

TIPS-

Remember that most governors with a screen off profile(Smartass, LulzactiveQ, OndemandAX) built in have a wake frequency (CPU immediately jumps to that frequency when screen on) is around 500-700 MHz, so try too keep your Max CPU limit at 800 MHz to prevent screen on delay. This is required as Xperia U has no 600 MHz intermediate CPU step, it has only 400 and 800. 400 is below the wake frequency so capping CPU at 400 MHz will cause lag during wakeup.

For me, using LulzactiveQ saves more power than SmartassV2 or Powersave. This is due to the fact that LulzactiveQ shuts off my second core much faster and much more dynamically than SmartassV2 of Powersave.

LulzactiveQ has a screen off profile of setting CPU speed to around 200-400 MHz while OndemandAX caps it at 500 MHz.

So OndemandAX is better for music as there is no tearing in playback when screen is turned off.

e. If you want to forcibly keep one core off (NOT RECOMMENDED. USE A HOTPLUGGING GOVERNOR INSTEAD) use XCore. It works on Xperia U and Xperia P. Check out the Play Store for further details.

4. RAM Management (Android does this on its own, usually. But you can help it)

a. NEVER use a Task Killer. Android kills tasks much more dynamically than your brain does :D

b. Delete all bloatware you do not need. This will prevent some background processes from being run and it will save some RAM.

c. Do not use a separate app for Facebook unless absolutely needed. (XDA App is fine :D)

d. That widget, sitting on your homescreen, which hasn't been touched for the past 1 week can be trashed.

5. GPS Superiority (You'll never use AGPS anymore)

a. Download an app called FasterGPS from the Play Store.(needs root)

b. Open the app and choose you continent and region. If your region isn't there, choose the closest region.

c. Get your ass out in the open and get a lock in less than a minute only on pure integrated GPS.

6. General Tweaks

a. Go to developer options in settings and set Animation Scale to 0.5x

b. Get a good statusbar mod (I recommend Xperia Tab n Grid Jelly Bean).

Why? So that you turn off the WiFi and BT and Packet Data when not required. I wouldn't do that earlier as I was too lazy to go all the way to settings to do so. Now I use the notification toggles and save some power

c. Turn OFF your phone and then charge it.

d. Use Lux Dash, an app to control your brightness. At night, set it to sub-zero to save power.

7. Physical Tips

a. Get a case for your phone. Incase you drop it, it will protect your phone.

b. I know you're tempted to take your phone to the pot and have fun but NO. People have lost phones like that.

c. Every week, clean your phone with a spectacle cloth.

d. Do not overstress your phone, or else you risk your hardware. I know they are designed to face all this but as Gandhiji said, compassion.

Hope these tips help you and your phone :D