How to Speed up Iphone 3g and 3gs running in ios 4.2.1

Frustrated in your iphone 3g / 3gs running in ios 4.2.1 then this topic is for you.
The first thing that slows down your iphone is the spotlight search. it indexed your messages , contacts , applications , Videos, Music , audiobooks, Notes , mail and events. but you can actually fix this by disabling the  the selected indexed items. Goto Settings , General , Home Button , then Spotlight search. then Uncheck all the checked items. then reboot your phone.. you will actually notice that your phone is much faster than it was before.

You can speed up your iphone 3g by holding down the power button and the home button for about 10 seconds. Do not release your fingers until the phone turns off then turns on.Do this regularly and you will notice the speed gained, also remove the themes in your iphone.. it slows down your phone because it runs in the background ;)
 iPhone has transformed cellphones. Phone companies and hardware-makers alike have rushed to  touchscreen interface, easy access to the Internet, and bustling App Store. The iPhone is no longer the mind-blowing, category-busting product it was in t2007. Our minds have been blown, the category was busted, and now competitors such as  Nokia, and Research in Motion are fighting back.