If you are planning to buy an iPhone 4S, it is important to erase the data from your old iPhone. And for that you need to know how to do that. Apple has solved this problem. You can find out how to erase all personal data from your old iPhone before upgrading to the iPhone 4S. Below are the tips to erase data from old iPhone
It is better if you perform a full firmware restore and set up your iPhone, iPod touch, or iPad as “new”. However, you can get it done even while you’re away from your computer. Following steps show you how to do it:
Tap the ‘Settings’ icon
Scroll down to the bottom and tap ‘Reset’
Tap ‘Erase All Content and Settings’
If you have a setup that requires a passcode, you’ll be asked to verify your credentials and then to confirm whether you actually want all the data in your iPhone to be erased completely. The procedure of emptying your iPhone can be time consuming depending on the amount of music, video, apps, etc. that you have stored in your iPhone. This is because Apple keeps writing over the data multiple times for security reasons.
Another noteworthy point is that if you have a jailbroken iPhone, it is important that you go through the full iTunes restore process. The reason behind it is that the permissions issues might prevent the data from being wiped out from the device.
Once the work is done you can simply give away or sell off your old iPhone without being worried that someone may get something you may have left behind.