While initially it was announced that no Google Android 4.0 ICS upgrade will be developed by Samsung for its older Galaxy devices. The company did make the upgrade available to Galaxy S2 users, and now Indian users have the upgrade officially pushed to them via Samsung Kies.
Steps to upgrade Samsung Galaxy S2 to latest officially available Google Andoid version is as follows :
The process is very simply, just connect your device to the PC and launch Samsung Kies software. Make sure you are connected to internet and it will prompt you for an firmware upgrade if one is available. Just follow the on-screen instructions as shown below.