Data sync uses up your battery.

[droidntn]

After a week of turning off data sync, and screen bright to 50% and FB refresh to every 2 hours, my X comes off the charger at 6:00 am and goes without a charge until 11 at nite.

 

[WAldenIV]

I easily get 16 hours or more out of a charge and I've never touched data sync.

 

[p08757]

Lots of different things affect battery life. Im glad you found something that workedfor you.