I may not have my own iPhone 3gs but i know that there are lots of people who are looking for ways on how to upgrade from iOS 3 to iOS4, so here are some of the information that are available in the net that might help you to upgrade your phone. But be careful for some known problems of iOs4 upgrade installation before to proceed.
Apple Insider says of the iOS 4 update:
Some of these features are limited to new hardware in the latest iPhone 4 (such as FaceTime video calling), while others are only available on last year’s iPhone 3GS and third generation iPod touch (including multitasking).
Here’s how to update your iPhone or iPod Touch, via CNET:
To get the update, simply connect your device to iTunes and follow the steps. It’s free for both iPhone and iPod Touch users–in the past the latter group users had to pay a small fee–though iOS 4 is not compatible with first generation models of either device. Also, remember that the iPhone 3G will not support the new multitasking feature.
You can check out Jaypee’s post about iOS4 Update Problems as follows :
- Photos synced with iPhoto turn are extremely blurry
- Update deletes all contacts, and backups will not restore them
- MMS no longer works
- Push notifications not functioning
- Auto-lock is set at one minute and the option to change this is greyed out
- Update fails and device reboots endlessly
Just make sure to check all consequences before proceeding, it is not bad to be techie and go with the flow but make sure to check the outcome and review of others.