depending on ur phone company, they all unlock over the phone, whether they charge u is up to them, but its the safest way. Im with three and they unlock for free. Call ur telco and just ask.
Hi,
i think there is no free sites for unlocking i phones regarding me. and its risk too.because if you go for free sites means the code generated for free will be sometimes goes wrong.so better go for paid sites.i know one online provider namely Ihav.net ,i came to know about this site through internet.i got experienced with this site.here they are providing good services at reliable rate.all you need is your IMEI number and they'll ask you some other details.after this they'll unlock your mobile through remote unlocking process its very simple one.then you can use your mobile using any network s your wish.if you need any information just visit this site and hope it'll be useful for you.
I was not able to find any free unlocking service for the mobile model that you have specified.To which network is your iPhone 4 locked to?I found that Simpleunlocking.com provides remote unlocking service and removes the network lock for iPhone 4 from major network provider in Australia.