Posted on: 22 June 2010 by Peter Dinh
1) If your iPhone is unlocked by a provider (e.g. AT&T in the US), it means that your SIM is activated, you can use your iPhone as a regular phone.
2) Jailbreaking is a hack way to allow your iPhone to run any software, including pirated apps. However, you can still use App Store to download apps that are approved by App. Please note that Jailbreaking is not the same as SIM unlocking - A successful SIM unlocking means that you can use your iPhone anywhere with any provider.
3) iOS4 can only run on iPhone 3G (with some limitations), iPhone 3GS and of course iPhone 4.
