I’ve complained quite a bit, here on this blog as well as on all of the social networking sites, that if you have an iPhone 3G and performed the upgrade to iOS4, your living in a painfull life. It can take 5+ seconds just to open your address book.
This video offers a nice comparison of 3.1.3 compared to iOS4x:
Where does this leave us 3G owners, Apple doesn’t offer a downgrade back to OS3.x. You could try a tricky hack to downgrade explained here: http://www.iphonehacks.com/2010/07/how-to-downgrade-iphone-3g-from-ios-4-to-iphone-os-3-1-3.html
The downgrade option seems sketchy at best and feels like you’ll need to be prepared to set aside some time to do it.
There is another option. It still wont be as zippy as it used to be, but the performance improvement I’ve seen is significant. The cure is turning off ‘Spotlight’ . Spotlight is the indexing app that runs in the background that enables the global search to work. To disable spotlight:
Home Button->Spotlight search
switch off all you don’t use. I rarely use search at all, so I felt confident turning all of them off. Then reboot your phone. It will make you feel like your back on OS 3.1.3 again.